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Biotechnology Bulletin 2017 Vol.33 Please wait a minute... For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails Select Metabolite Biosensor：A Useful Synthetic Biology Tool to Assist the Construction of Microbial Cell Factory ZHOU Yi-kang, WU Yi-nan, WANG Tian-min, ZHENG Xiang, XING Xin-hui, ZHANG Chong Biotechnology Bulletin    2017, 33 (1): 1-11.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.001 Abstract （296）   HTML    PDF（pc） （1614KB）（1181）       Knowledge map    Save Metabolite biosensor,which represents a useful synthetic biology tool,can sense the concentration of intracellular metabolites and then transfer it into specific signal output,showing great potential in the construction of microbial cell factory. It generally consists of two components,biological recognition element and signal output element. The former,typified by regulatory elements,is ubiquitous in nature,such as transcription factor and riboswitch,and has diverse response mechanism. The output can be fluorescence signals,fitness,pathway activation or silence,and so on. Here we reviewed recent progresses about applications of metabolite biosensor in the construction of microbial cell factory,including high-throughput screen/selection,dynamic control and non-genetic selection. We also discussed the effects of the metabolite biosensor performance in application and focused on the opportunities and challenges we might meet in practice. Reference | Related Articles | Metrics Select Key Technologies and Applications of Synthetic Biology YANG Ju, DENG Yu Biotechnology Bulletin    2017, 33 (1): 12-23.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.002 Abstract （426）   HTML    PDF（pc） （2202KB）（762）       Knowledge map    Save Synthetic biology is to reconstruct the existing natural system by building standardized components and modules and synthesize new artificial life system from scratch under the guidance of engineering design ideas.With the help of gene recombination technology and genome editing technology,we can program life system to comply special functions. After realizing modular analysis of metabolic pathways and optimizing the combination between the components we can synthesize chemicals with excellent patterns. At present,people have made great progress in the fields of energy,chemical industry and medicine. Synthetic biology will bring great changes to people’s life and will continue to be the hotspot of research.The review describes the major applications and the key technologies of synthetic biology in genome editing and modular representation. Reference | Related Articles | Metrics Select Research Advance on Biosynthesis of Aromatic Amino Acids and Their Derivatives SHEN Xiao-lin, YUAN Qi-peng Biotechnology Bulletin    2017, 33 (1): 24-34.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.003 Abstract （275）   HTML    PDF（pc） （1924KB）（879）       Knowledge map    Save Bioengineering has been used to produce various of value-added products including fine chemicals,bulk chemicals,pharmaceuticals and nutraceuticals using sustainable materials. Synthetic biology is the foundation of bioengineering which combined functional genomics,computational biology with system biology to createnovel products and optimize bioprocess. In the past decades,many powerful tools developed from synthetic biology has been used in microorganisms,plants and animals. In this review,we summarize the synthesis of aromatic amino acids and its derivatives in microorganisms and review the recent advances in bio-production of value-added chemicals using synthetic biology. Reference | Related Articles | Metrics Select Applications of Synthetic Biology in the Research of Natural Product WANG Li-ping, LUO Yun-zi Biotechnology Bulletin    2017, 33 (1): 35-47.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.004 Abstract （346）   HTML    PDF（pc） （3743KB）（773）       Knowledge map    Save As an important source of clinical medicine and new drug candidate,natural product plays an essential role in therapeutic and pharmaceutical industry. However,traditional methods for natural product discovery constrain the development of new compounds at certain extent,and identifying and refactoring the biosynthetic pathways of natural products provided new thoughts for the discovery of new natural product. Currently,with the prosperous development of bioinformatics and synthetic biology technologies,a new era of natural product discovery and engineering can be foreseen. Here,we summarize recent advances on the strategies of genetic recombination and gene cluster regulation related to synthetic biology techniques,and discuss their applications and issues in studying natural products. Reference | Related Articles | Metrics Select Optimization Strategies for Synthetic Biological Systems of Natural Products KUANG Xue-jun, ZOU Li-qiu, SUN Chao, CHEN Shi-lin Biotechnology Bulletin    2017, 33 (1): 48-57.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.005 Abstract （230）   HTML    PDF（pc） （1105KB）（572）       Knowledge map    Save Natural products have become an important source of new drugs. However,there are some deficiencies while producing complex natural products by classical organic synthesis,one measure to efficiently make up those deficiencies is to apply synthetic biology in the biosynthesis of natural product,i.e.,designing and reconstructing efficient biosynthetic pathways of target compounds,re-engineering it in host cells,and producing target compounds by fermentation. However,achieving the yield of target product to the industrial level through technology of synthetic biology is still very challenging though there have been advances in synthetic biology. Here,we review various pathway optimization strategies for the synthetic biological systems of natural products. Via optimization technologies of fine-tuning individual component,exogenous metabolic pathways,the chassis systems,and fermentation conditions,the synthetic biological system may be optimized,and the yield of target product may be maximized,thus providing continuous,stable and economical raw material supplies for the manufacture of complex natural products while source is rare,and promoting the research and development of new drugs similar to natural products Reference | Related Articles | Metrics Select Application of Switch for Synthetic Biology in Metabolic Engineering PANG Qing-xiao, LIANG Quan-feng, QI Qing-sheng Biotechnology Bulletin    2017, 33 (1): 58-64.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.006 Abstract （217）   HTML    PDF（pc） （2549KB）（609）       Knowledge map    Save Translational switches for synthetic biology are mainly used to regulate gene expression in the field of metabolic engineering research. Traditional metabolic engineering regulates the expression of specific genes by using knockout and overexpression. However,the knockout of genes usually leads to the decrease in growth,therefore,we need to close and activate the expression of specific gene at proper time,and translational switche for synthetic biology is the key tool to solve such issue. At present,light-controlled switch,temperature-induced switch,toggle switch,and riboswitch are commonly used in metabolic engineering,of which the toggle switch and riboswitch present a great advantage in the dynamic regulation of gene expression. In this paper,several kinds of translational switches for synthetic biology and their applications in metabolic engineering are reviewed. Reference | Related Articles | Metrics Select Research Progresses in the Synthetic Biology of Terpenoids SUN Li-chao, LI Shu-ying, WANG Feng-zhong, XIN Feng-jiao Biotechnology Bulletin    2017, 33 (1): 64-75.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.007 Abstract （845）   HTML    PDF（pc） （1825KB）（3403）       Knowledge map    Save The terpenoids represent the largest class of natural products with biological activities of antitumor and anti-allergy,thus they have been widely applied in the area of food,cosmetics and medical health,presenting huge potential and broad market prospects. Recent years,researchers applied functional genomics and metabonomics approaches to deeply study the biosynthesis pathways of terpenoids,providing tons of data for their synthetic biology. The construction of engineered yeasts using synthetic biology enabled the efficient synthesis of multi-target terpenoids,and highly improved the overall production level. Thus,the synthetic biology approach is expected to be an efficient way of producing plant-derived terpenoids. First,we introduced the concept of synthetic biology,summarized the important functions and applications of plant-derived terpenoids,briefly reviewed the biosynthesis pathways,and concluded the alternative production ways. Then,we discussed the design strategies of synthetic biology for terpenoids thoroughly. Finally,we elaborated the advances on the biosynthetic biology of varied terpenes with common terpenes as the studied cases. Reference | Related Articles | Metrics Select Advances on Applications of Synthetic Biology and Directed Evolution in Microbial Systems GUO Yuan, ZHAO Zhong-lin Biotechnology Bulletin    2017, 33 (1): 76-82.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.008 Abstract （257）   HTML    PDF（pc） （1953KB）（666）       Knowledge map    Save Nowadays,there are needs to engineer complex multi-genic traits in modern biotechnology applications;however,our capability to rationally engineer them is limited by the lack of knowledge on the genetic basis of complex phenotypes. Using synthetic biological measures,complex phenotypes can be engineered at the systems level,and via directed evolution strategies the whole biological system may be driven toward desired phenotypes without requiring the knowledge of the genetic basis of the targeted traits. The latest developments in the synthetic biology accelerate the directed evolution cycle,facilitating engineering of increasingly complex traits in biological systems. Herein,the recent advances on synthetic biology in directed evolution of complex traits in microbial systems are reviewed. Reference | Related Articles | Metrics Select Ultra-high-throughput Screening System Based on Droplet Microfluidics and Its Applications in Synthetic Biology MA Fu-qiang, YANG Guang-yu Biotechnology Bulletin    2017, 33 (1): 83-92.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.009 Abstract （314）   HTML    PDF（pc） （3139KB）（738）       Knowledge map    Save The construction of a highly efficient synthetic biological system requires laborious screening work to optimize the performance of artificial system. Droplet microfluidic techniques miniaturize traditional screening systems,in a uniform pico-liter micro-reactors,the detection of enzymatic reactions and metabolites at single-cell level were measured and screened,thus it can screen genes/cells at a speed up to >108 events per day,which greatly improves the optimizing capability of catalytic parts and engineered strains. Herein,the technical backgrounds while applying droplet microfluidics in synthetic biology system are summarized,focusing on the fluorescence-coupling strategies in the detection of target enzyme reactions and metabolites. Moreover,recent progress on employing droplet microfluidics in the screening and engineering of catalytic parts and metabolic pathways is reviewed,the developing trends of this field are discussed. Reference | Related Articles | Metrics Select The Development of Engineered Saccharomyces cerevisiae for Biomass Conversion LIU He, ZHU Jia-qing, ZONG Qiu-jin, LI Bing-zhi, YUAN Ying-jin Biotechnology Bulletin    2017, 33 (1): 93-98.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.018 Abstract （210）   HTML    PDF（pc） （842KB）（515）       Knowledge map    Save With the increasing demand of oil,coal and other nonrenewable resources,it is urgent to develop the use of renewable and eco-friendly energy resources. The production of cellulosic ethanol from biomass has the advantage that the raw material is renewable and the cost is low. Saccharomyces cerevisiae has been most widely used for biomass conversion,with the characters of being easy for genetic engineering operation and high inhibitor tolerance. The two major challenges during the process of S. cerevisiae used for biomass conversion are the utilization of xylose and inhibitor tolerance. The major emphasis of this review will be the development of engineering Saccharomyces cerevisiae to improve inhibitor tolerance and speed up the transformation of xylose utilization. Reference | Related Articles | Metrics Select Research Progress on the Synthesis of S-adenosyl-L-methionine in Microorganism ZHAO Wei-jun, HUANG Lei, XU Zhi-nan Biotechnology Bulletin    2017, 33 (1): 99-105.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.010 Abstract （302）   HTML    PDF（pc） （1272KB）（687）       Knowledge map    Save S-adenosyl-L-methionine（SAM）as an important metabolite exists in all cell types of living organisms,presents promising effects on liver diseases and depressive syndromes without any side effects,thus,it is greatly demanded in medical market. Recently,broad studies on biosynthesis of SAM have been conducted by scholars in the world. On the one hand,fermentation strategies based on traditionally producing SAM were further improved;on the other hand,different rational breeding programs were developed,such as fine tuning host’s metabolic network or screening strains by synthetic gene circuit. In this paper,progress in the research of S-adenosyl-L-methionine production is summarized,and the significances and issues while efficiently producing SAM by microorganism are discussed,aiming at providing the guides for improving SAM productivity at an industrial scale. Reference | Related Articles | Metrics Select Research Progress for Genetic Modification of Butanol-producing Clostridia ZHANG Chao, WANG Yi-qiang, WANG Qi-ye, HUANG Rui-chun, MI Xiao-qin Biotechnology Bulletin    2017, 33 (1): 106-113.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.011 Abstract （216）   HTML    PDF（pc） （1230KB）（351）       Knowledge map    Save Butanol-producing Clostridia as butanol fermentation strains have been studied frequently in recent years. As a new renewable energy sources,butanol has obviously more advantages than ethanol. Therefore,it is of great significance to study gene modification of butanol-producing Clostridia. In this review,from three aspects of key genes,glycolytic pathway,and butanol tolerance,we introduced the latest research progress on gene modification of butanol-producing Clostridia. Meanwhile,we discussed the issues in the current research,and put forward suggestions on how to improve the butanol yield,aiming at providing some new ideas for the researchers. Reference | Related Articles | Metrics Select Research Progresses on Riboswitches and Their Applications in Antimicrobials SHENG Shu-yue, CHEN Yue, ZHANG Xing-mei, SHI Yu-sheng Biotechnology Bulletin    2017, 33 (1): 114-119.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.012 Abstract （273）   HTML    PDF（pc） （824KB）（534）       Knowledge map    Save Riboswitch is a class of RNA elements that regulate expressions of corresponding downstream genes and then control cells’ functions by binding with nucleic acids,amino acids,metal ions,derivatives of carbohydrates and coenzymes. Riboswitch has been a research focus in gene regulation in recent years and has been being used in mass screening bacterial strains,constructing new biosensors and as new target of antimicrobials. In this paper,recent research progresses on several important classes of riboswitches（such as purine riboswitch,lysine riboswitch,c-di-GMP riboswitch,glmS riboswitch,TPP riboswitch,FMN riboswitch,etc.）in targeting of antimicrobials are mainly reviewed. Reference | Related Articles | Metrics Select Activity Comparison of the Artificial Hybrid Promoter with Its Native Promoter in Saccharomyces cerevisiae TANG Rui-qi, XIONG Liang, BAI Feng-wu, ZHAO Xin-qing Biotechnology Bulletin    2017, 33 (1): 120-128.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.013 Abstract （256）   HTML    PDF（pc） （1843KB）（468）       Knowledge map    Save The responses of promoter strengths of artificial TEF1 promoter（PaTEF1）and native promoter PTEF1 as well as PTDH3 were comprehensively compared. The strength of PaTEF1 was not always higher than PTEF1,but varied along with the genetic background of host,medium,and cell growth phase. Among the three investigated hosts,PaTEF1 showed the highest strength in BY4741,while the lowest in LX03. The strengths of PaTEF1 were 1.4-4.6 and 0.9-2.0 times of those of native promoters（PTEF1 and PTDH3）in YPD100 medium,respectively. The activities of PaTEF1 in YPE（5% and 7%）were 0.7-1.3 and 0.8-1.3 times of PTEF1 and PTDH3. The activity of PaTEF1 in YPE was 1.7-2.0 times of that in YPD100,whereas 2.7-7.1 and 1.3-3.4 times for PTEF1 and PTDH3,respectively. The activities of the promoters in YEP were higher than those in YPD100,however,the activity variation of artificial promoters was less than that of native promoter. In addition,the variation trends of promoter strengths from early-log to mid-log phase and from mid-log to stationary phase varied in different host strains. Reference | Related Articles | Metrics Select Biosynthesis of Valerena-4,7（11）-diene in an Engineered Escherichia coli Strain LIU Chang, YIN Hua, ZHUANG Yi-bin, LIU Tao Biotechnology Bulletin    2017, 33 (1): 129-134.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.014 Abstract （194）   HTML    PDF（pc） （2149KB）（331）       Knowledge map    Save Valerena-4,7（11）-diene is a bicyclic sesquiterpene and shows particularly profound sedative,stress reducing and anxiolytic effects,and it could be used to treat attention deficit hyperactivity disorder（ADHD）and other mental illness. To achieve the de novo biosynthesis of valerena-4,7（11）-diene in Escherichia coli,eight genes of Saccharomyces cerevisiae involved in converting acetyl-CoA into farnesyl diphosphate（FPP）from mevalonate pathway and the valerena-4,7（11）-diene synthase（VoTPS）gene from Valeriana officinalis were co-overexpressed in BL21（DE3）. Adopting the bipolar fermentation method of water phase and organic phase,the valerian-4,7（11）-diene was detected in organic phase by GC-MS,indicating that the synthesis of valerian-4,7（11）-diene was achieved initially in theE. coli. After primarily optimizing the IPTG concentration,the temperature of protein induction and choice of varied organic phases,the fermentation conditions were determined as follows：protein induced temperature was 20℃,the concentration of IPTG was 0.1 mmol/L,and organic phase was dodecane. Reference | Related Articles | Metrics Select Biosynthesis of 3,4-dihydroxymandelic Acid in an Engineered Escherichia coli Strain LI Xiao-lin, ZHOU Wei, ZHUANG Yi-bin, LU Fu-ping, YIN Hua Biotechnology Bulletin    2017, 33 (1): 135-140.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.015 Abstract （300）   HTML    PDF（pc） （2700KB）（389）       Knowledge map    Save 3,4-dihydroxymandelic acid,an important pharmaceutical and spices intermediate,possesses strong antioxidative and radical scavenging activities. To achieve the de novo biosynthesis of 3,4-dihydroxymandelic acid in Escherichia coli,the genes of hydroxymandelate synthase（HmaS）from Streptomyces coelicolor and 4-hydroxyphenylacetate 3-hydroxylase（HpaBC）from E. coli were cloned into pTrcHisB and overexpressed in an engineered E. coli strain MG1655/ΔA. After induction of IPTG and optimization of the inducing temperature,the yield of 3,4-dihydroxymandelic acid reached 240 mg/L in shake flask after 36 hours fermentation,laying a foundation for the large-scale fermentation production of 3,4-dihydroxymandelic acid . Reference | Related Articles | Metrics Select Regulatory Effects of Gene sco1135 on the Sporulation and Secondary Metabolite Synthesis of Streptomyces coelicolor M145 MA Jun-xia, ZHANG Pei-pei, WANG Shi-li, CAO Guang-xiang, Biotechnology Bulletin    2017, 33 (1): 141-147.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.016 Abstract （200）   HTML    PDF（pc） （2305KB）（625）       Knowledge map    Save This work aims to study the effects of deletion and mutation of gene sco1135 on the morphogenesis and secondary metabolism in Streptomyces coelicolor strain M145. Recombinant plasmid pSJ1135 was obtained by PCR-targeting. Gene deletion mutant of sco1135（△sco1135）was acquired by introducing the recombinant plasmid into the Streptomyces coelicolor M145 via conjugation and transformation,and the complemented strain △sco1135com was constructed using the vector pMS82. Using pMS82 as a control,the phenotypes of the parental wild strain（M145）,mutant strain（△sco1135）and complemented strain（△sco1135com）were analyzed and observed with quantitative antibiotics. The results of phenotypic analysis and observation with quantitative antibiotics revealed that the sporulation in △sco1135 obviously delayed than that of the wild type M145 on YBP medium;while the actinorhodin（ACT）production in △sco1135 increased to 2-3 folds of that in M145. The transcriptions of some sporulation-related genes decreased by 50%-75% in △sco1135 at 48 h,while the transcriptional expressions of genes related to ACT in △sco1135 increased to 13-20 folds at 72 h,compared to the M145. Conclusively,sco1135 is involved in regulating the sporulation in M145 and also the production of secondary metabolite ACT. Reference | Related Articles | Metrics Select Construction of 5-aminolevulinic Acid Synthesis Pathway and Optimization of Fermentation by Corynebacterium glutamicum RAO De-ming, ZHANG Liang-cheng, CHEN Jiu-zhou, SUN De-hu, SUN Cun-min, ZHENG Xiao-mei, ZHENG Ping, DIAO Ai-po Biotechnology Bulletin    2017, 33 (1): 148-156.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017.01.017 Abstract （279）   HTML    PDF（pc） （2017KB）（599）       Knowledge map    Save 5-aminolevulinic acid（ALA）is a natural non-protein amino acid and has been widely applied in agriculture and medicine. This study aimed to construct the systhesis pathway of C4 ALA in Corynebacterium glutamicum and optimize its fermentation process. First,efficient C4 ALA synthesis pathway was established in C. glutamicum by over-expressing the ALA synthase（ALAS）from Rhodopseudomonas palustris. Then,the ALA fermentation process with flask was optimized from four factors：fermentation medium,concentration of inducer,substrate concentration,and initial inoculum dosage. As results,the ALA yield of the strain 13032/pZWA1 over-expressing HemA was 1.41 g/L,up to 67.14 folds compared with the control strain. The optimal ALA fermentation condition was M9 media using yeast extract as nitrogen source with 5% inoculum size,0.1 mmol/L IPTG to induce the experession of HemA,and the concentration of glycine must be at 4 g/L. After optimization,ALA yield reached 3.28 g/L in a shaking flask and increased 132.62% than before. In conclusion,under the optimal fermentation condition,the ALA yield in a 5 L bioreactor fermentation was 10.08 g/L,which was the highest ALA yield by one-step fermentation of C. glutamicum reported so far. Reference | Related Articles | Metrics Select Research Progress on the Functional Microorganisms in Enhanced Biological Phosphorus Removal(EBPR) Systems WEI Ru-ping, YAN Cheng, YANG Xin-yan, HE Xiao-yun, WANG Xin, YANG Liu-yan Biotechnology Bulletin    2017, 33 (10): 1-8.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0558 Abstract （326）   HTML    PDF（pc） （1100KB）（539）       Knowledge map    Save Phosphorus emission from human activities is one of the major causes of water eutrophication. The technology of enhanced biological phosphorus removal（EBPR）has been widely applied for removing phosphorus from wastewater due to its advantages of economy and sustainability. The key to the efficient and stable operation of EBPR system is that the microbial community in the system is reasonable and functional. For deeply understanding the mechanism of phosphorus removal and the efficient and stable operation of EBPR system，a large number of studies were conducted on the microbial community structure and main functional microorganisms in the system. In addition to polyphosphate-accumulating organisms（PAOs），the EBPR system also includes non-PAOs，mainly glycogen-accumulating organisms（GAOs）and some auxiliary bacteria. Nowadays，more and more types of functional polyphosphate-accumulating microorganisms were identified，and the most studied PAOs and GAOs were Accumulibacter and Defluviicoccus respectively. PAOs and GAOs compete or cooperate under different environmental conditions，but it is still controversial whether PAOs may exhibit the metabolic properties of GAOs under certain conditions. Besides the traditional factors such as carbon source，pH and temperature，the effects of exogenous pollutants，like antibiotics and heavy metals，on functional microorganisms in EBPR system also exist. The traditional separation methods，blue/white screening and the method of artificial construction of gene engineering bacteria have been applied for acquiring efficient PAOs. The development of modern molecular biology technology provides advanced and reliable technical means for the research of functional microorganisms in EBPR system，and the efficient removal of phosphorous by constructing high-performance polyphosphate-accumulating microorganisms will be an important trend in future increasing bio-removal phosphorus efficiency from actual wastewater. Reference | Related Articles | Metrics Select Microbial Remediation of Soil Heavy Metal and Organic Pollutants：Bioaugmentation and Biostimulation HAO Da-cheng, ZHOU Jian-qiang, HAN Jun Biotechnology Bulletin    2017, 33 (10): 9-17.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0294 Abstract （330）   HTML    PDF（pc） （1579KB）（1193）       Knowledge map    Save Green technologies，e.g.，bioaugmentation and biostimulation，are cost effective and eco-friendly，and are becoming Rosetta Stone for the remediation of soil heavy metal and organic pollutants. Various bacteria，fungi and their consortia can be combined with physical and chemical techniques for the targeted remediation of soil organic contamination，heavy metal contamination and combined pollutions. This review exemplifies the representative studies within the recent five years，summarizes the screening of microbial strains from multiple sources and their potentials in transforming/degrading various types of pollutants，and highlights their applications in the case studies of laboratory，greenhouse and field conditions. The complexity of microbial remediation is ascribed to not only the variations of physiological and metabolic traits，but also numerous environmental factors，including abiotic factors，e.g.，pH，temperature，type of soil，pollutant concentration，content of water and organic matter，additional carbon and nitrogen sources，and biotic factors，e.g.，inoculum size，interactions between the introduced strains and autochthonous microbes，and the survival of inoculants. Prospects of combined remediation and the applications of molecular methods are also presented. Reference | Related Articles | Metrics Select Review of Petroleum Hydrocarbon Pollution and Microorganism Remediation GUO Ping, LI Hong-na, LI Feng, YE Jing Biotechnology Bulletin    2017, 33 (10): 18-25.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0799 Abstract （265）   HTML    PDF（pc） （1198KB）（537）       Knowledge map    Save petroleum hydrocarbon pollution is one of the most severe environmental pollution in abroad and china，the restoration of environment ecology and remediation of petroleum hydrocarbon pollution by microorganism technology have revealed advantage in past practice. With the economic development rapidly，the quickly increased requirement for petroleum hydrocarbon highlights the pollution problem. The challenge is regarding to this technology under more severe pollution and environmental deterioration. This paper address the trend of petroleum pollution and technology application，the analysis of petroleum hydrocarbon degradation microorganism classification，the molecular mechanism of petroleum hydrocarbon degradation by microorganism and the application of microorganism remediation technology，and cater for understanding the challenge more further. Reference | Related Articles | Metrics Select Research Progress on in situ Detection Methods of Microorganisms SONG Wei-feng, LI Ming-cong, GAO Zheng Biotechnology Bulletin    2017, 33 (10): 26-32.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0550 Abstract （239）   HTML    PDF（pc） （1203KB）（769）       Knowledge map    Save As major participants in ecosystem material cycle and energy flow，microorganisms play an important role in the ecosystem. However，the proportion of the cultivable microorganism under the existing technology is very small，which limits the exploit of microbial resources. At present，there are a number of approaches that can avoid the problem of uncultured microorganisms，which are designed to study in situ microbial activity. Regarding this，we summarized some research methods of studying in situ microbial ecology，allowing it convenient to reasonably use these methods in the future. This article introduces the corresponding microbial detection methods of BrdU-labeling，DNA-SIP，fluorescence in situ hybridization（FISH），and environmental transcriptome from DNA level，RNA level and protein level，respectively，and compares their advantages and disadvantages. It also introduces how to apply these methods combined with popular high-throughput sequencing and single cell sequencing technology to capture the in situ activity of microbial groups. At the same time，comparing the characteristics of these methods，so that we can more clearly understand the choice of different methods under different scenarios. These modified methods combined with other methods will be conducive to solve many have-been or will-happen problems in the study of microbial ecology. The ecosystems on the earth are complex and huge，in which the microbial populations vary. A variety of in situ detection methods have made a more realistic and effective description for the physiology and ecology of microorganisms，which will become a powerful tool for the study of microorganisms. Reference | Related Articles | Metrics Select Research Progresses on Lignocellulose Degradation by a Thermophilic Anaerobic Bacterium Caldicellulosiruptor bescii CHU Yin-di, SU Xiao-yun Biotechnology Bulletin    2017, 33 (10): 33-39.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0533 Abstract （239）   HTML    PDF（pc） （1246KB）（287）       Knowledge map    Save As a gram-positive anaerobic bacterium isolated from hot spring，Caldicellulosiruptor bescii has strong ability in degrading lignocellulose. It can rapidly grow on a variety of model plant cell wall polysaccharide compounds such as the crystalline cellulose avicel，xylan or even on unpretreated lignocellulose such as switchgrass as sole carbon source. Moreover，this bacterium has an unusual ability of anaerobic degradation of lignin. The genomic annotation showed that most of the proteins encoded by this bacterium were multivariate bi-functional enzymes，i.e.，the N-terminal and C-terminus of the polypeptide chain were glycoside hydrolases of different families，with 2-3 carbohydrate binding domains. The genes encoding enzymes of degrading cellulose were concentrated in a plant cell wall polysaccharide degradation gene cluster，such as cellulase/xylanase，cellulase/mannanase，cellulase/xyloglucanase，etc. The xylanase of C. bescii belonged to the GH10 family，whose specificity of the enzyme was broad，and the homology of the amino acid sequence was between 18.7% and 59.5%. The genus Caldicellulosiruptor evolved a series of mechanisms that allowed glycoside hydrolyses to absorb better to substrates，bacteria and lignocellulose，thereby facilitating the enzymatic hydrolysis of lignocellulose. There were 12 proteins containing SLH domain，and the newly discovered adhesion protein Tāpirin in C. bescii may be involved in the absorption and utilization of lignocellulose. In this paper we review the current progresses in exploring the genome of C. bescii for novel glycoside hydrolases targeting plant cell wall and the associated molecular mechanisms，which are of great significance for the design and optimization of efficient and multi-function lignocellulose degradation enzymes. Reference | Related Articles | Metrics Select Research Progress of New Biomarker Gene of phoH for Bacteriophage Genetic Diversity LI Xiang, SUN Yan, WANG Xin-zhen, LIU Jun-jie, WANG Guang-hua Biotechnology Bulletin    2017, 33 (10): 40-45.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0725 Abstract （209）   HTML    PDF（pc） （1523KB）（455）       Knowledge map    Save Bacteriophages（phages）are the simplest biological entities，which play important roles not only in the regulation of their host communities and horizontal transfer of genetic materials，but also in the element biogeochemical cycles. Although the importance of phages is increasingly being paid attentions by researchers，however there are still great limitations on the study of phage gene diversity until now. Therefore，the work of finding and verification of a suitable molecular marker gene for studying the genetic diversity of phage in natural environments is one of the hotspots of virus ecology. In this paper，a new molecular biomarker gene of phage auxiliary metabolic gene of phoH was introduced，and the recent advances in using this gene to reveal the phage genetic diversity in marine waters，paddy floodwaters and desert hypoliths are reviewed. Results showed that the distribution of phage phoH gene was closely related to its living environments，and phoH clones were divided into several groups according their obtained environments. In the end of the paper，the future research directions of phage phoH gene are also proposed. Reference | Related Articles | Metrics Select Applications of Genomics，Proteomics and Metabolomics in Microbial Degradation of PAHs KONG De-kang, WANG Hong-qi, XU Jie, LIU Zi-li, WU Xiao-xiong Biotechnology Bulletin    2017, 33 (10): 46-51.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0368 Abstract （333）   HTML    PDF（pc） （1267KB）（683）       Knowledge map    Save Genomics，proteomics and metabolomics are important components of systemic biology，which are the emerging disciplines developed in recent years. With the development of life sciences，genomics，proteomics and metabolomics have been developing rapidly，and widely used in various fields of environmental microbiology，and become an indispensable part of studying polycyclic aromatic hydrocarbons（PAHs）microbial degradation. In this paper，the latest research progresses on the mechanisms of microbial degradation of PAHs and the metabolic pathways in three disciplines are reviewed，and the application prospects and challenges of the three disciplines in the PAHs biodegradation are discussed. Reference | Related Articles | Metrics Select Research Progress on Ecotoxicity and Microbial Degradation of Strobilurin Fungicides FENG Yan-mei, FAN Xing-hui, ZHAN Hui, TENG Shi-yu, YANG Fang, CHEN Shao-hua Biotechnology Bulletin    2017, 33 (10): 52-58.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0581 Abstract （289）   HTML    PDF（pc） （1874KB）（340）       Knowledge map    Save The widely used strobilurin fungicides in agriculture have become a public concern because of their heavily environmental contamination and toxic effects on mammals. Such concerns，therefore，highlight the critical need for effective and advanced remediation technologies for the removal of strobilurin residues. Recently，bioremediation has emerged as a great potential alternative to eliminate pesticide residues because of its effective，low-priced，and eco-friendly properties. In this review，we summarized the research status of ecotoxicity of strobilurins and their microbial degradation. The main metabolites and the proposed degradation pathways of strobilurins were investigated. Moreover，the deficiencies of microbial degradation and the future development were discussed. These results may lay a solid foundation for developing new and safe measures for solving pollution hazard from strobilurin-like residues. Reference | Related Articles | Metrics Select Research Progress on Bioaccumulation of Heavy Metals in Wastewater by Filamentous Fungi MA Yan, YU Xiao-bin Biotechnology Bulletin    2017, 33 (10): 59-63.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0516 Abstract （255）   HTML    PDF（pc） （1251KB）（384）       Knowledge map    Save Wastewater containing heavy metals is the one that most seriously pollutes environment and damages human health. Bioaccumulation of heavy metals by filamentous fungi is an important mean for processing heavy metal wastewater，and it has been a hot research topic in recent years. Firstly，the advantages and disadvantages of conventional methods of removing heavy metals from wastewater were reviewed，including chemical precipitation，ion exchange and adsorption. Among them，biosorption owns special advantages，such as low price and low consumption of biosorbents，its high effectiveness in absorbing the heavy metal ions，wide application and biosorbents reusable，thus biosorption is particularly suitable for the treatment of trace heavy metal wastewater. Secondly，the types of filamentous fungi that were applied to the removal of heavy metals were introduced，such as Rhicopus（Pb2+，Cd2+，and Cr5+），Mucor（Pb2+，Ni2+，Cd2+，and Zn2+），Aspergillus（Pb2+），Trichoderma（Zn2+ and Pb2+），and Basidiomycota（Cu2+，Pb2+，and Cd2+）；they all presented ideal results in removing heavy metals. Thirdly，the mechanisms of bioaccumulation were summarized，mainly about extracellular，cell surface，and intracellular absorption of heavy metals. Lastly，the several factors affecting the efficiency of removing heavy metals（pH，initial concentration of heavy metal ions，proportion of adsorbent，temperature，and coexisted ions）were discussed，as well as the future of studying filamentous fungi was prospected. It is aimed at expanding the application of filamentous fungi in the heavy metal accumulation from wastewater and laying a foundation for initiating new types of filamentous fungi in accumulating heavy metal from wastewater. Reference | Related Articles | Metrics Select Research Progress on Electricigens in Microbial Fuel Cell ZHANG Xia, XIAO Ying, ZHOU Qiao-hong, WU Zhen-bin Biotechnology Bulletin    2017, 33 (10): 64-73.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0222 Abstract （273）   HTML    PDF（pc） （1515KB）（621）       Knowledge map    Save Microbial fuel cell（MFC），one of the novel environmental and energy technologies，is attracting attention of numerous researchers. MFC is a device that utilizes microorganisms to convert chemical energy from organic matter into electrical energy. As a biocatalyst，electricigens play a key role in the development of MFC. Different kinds of electrogenes have different electron transfer mechanism and ability，affect the production performance of MFC directly，then determine the MFC performance and application in engineering practice. Any waste water，sludge，and sediment containing a large amount of microorganisms，try to screening high efficient electrogenes isolated from different environment is expected to promote the further perfect of MFC，so as to accelerate its application in the environment. The latest progress of electricigens in MFCs from several aspects were summarized，including of the development of MFC’s operation，the electricigens species and their electron transfer mechanism，specifically including the screening methods of electricigens，types and the related technology research. Finally，the main research trends of electricigens and the potential application of MFC in the future are also listed，aiming at providing the corresponding theoretical basis and new ideas for the screening and application of electricigens. Reference | Related Articles | Metrics Select Study Progress on Microorganism in Constructed Wetlands WANG Yu-xuan, WEI Wei, LI Ping-ping, ZHAO Yun, FU Wei-guo Biotechnology Bulletin    2017, 33 (10): 74-79.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0125 Abstract （241）   HTML    PDF（pc） （1604KB）（411）       Knowledge map    Save Constructed wetland is a sewage processing technology engineering developed rapidly since the late 1970s. It has the advantages of low investment，low running cost，low-level maintenance technology and low energy consumption. Currently，it has been used to process various types of waste-water. Constructed wetland is a composite system composed of matrix，plant，and microorganism，in which microorganisms play an important role in the process of waste-water purification. This paper introduces the research progress of microorganisms in the constructed wetland system from the diversity and function of microbial community，and further gives the research prospects in this field，aiming at providing information and reference for relevant researches in this field. Reference | Related Articles | Metrics Select Research Progress on Microbial Quorum Quenching Enzymes and Their Control of Plant Diseases FAN Xing-hui, WANG Hui-shan HE, Jie-hua YE, Tian YANG, Fang CHEN Shao-hua Biotechnology Bulletin    2017, 33 (10): 80-87.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0223 Abstract （364）   HTML    PDF（pc） （1766KB）（348）       Knowledge map    Save The phenomenon of information exchanging through signal molecules between microbial cells is the Quorum Sensing（QS）. QS is widely present in microorganisms，and can modulate the expression of specific genes，especially virulence factors in pathogenic microorganisms. Quorum Quenching（QQ）is a new therapeutic strategy of plant diseases based on QS. QQ can be achieved by interfering QS from inhibiting the synthesis or detection of the signal molecules，or by enzyme-catalyzed degradation or modification of the signal molecules. Degrading signal molecules by using QQ enzymes is one of the most effective and nontoxic ways of QQ. So far，QQ enzymes of various microbial signaling molecules have been reported，especially N-acyl homoserine lactones（AHLs）and cis-11-methyl-2-dodecenoic acid were deeply investigated. In this review，we summarize and analyze the research status，deficiencies and the future development of QQ enzymes and their control of plant diseases，for laying a solid foundation for developing new，green and safe measures of disease control. Reference | Related Articles | Metrics Select Research Progresses on Strain Construction of Xylose Isomerase-based Recombinant Xylose-fermenting Saccharomyces cerevisiae LI Yun-cheng, MENG Fan-bing, GOU Min, SUN Zhao-yong, TANG Yue-qin Biotechnology Bulletin    2017, 33 (10): 88-96.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0448 Abstract （224）   HTML    PDF（pc） （1958KB）（226）       Knowledge map    Save It is of utmost significant to construct industrial xylose-fermenting Saccharomyces cerevisiae strains for lignocellulosic bioethanol production through the heterologous expression of xylose metabolic pathway. Xylose isomerase pathway is regarded as the most promising pathway expressing in S. cerevisiae，since there is no xylitol accumulation resulted from the coenzyme imbalance in xylose redox pathway. In heterologous expression of xylose isomerase，selecting an industrial S. cerevisiae strain as initial strain is of outstanding advantages for lignocellulosic bioethanol production. Concurrently，improving the expression efficiency of xylose isomerase gene（xylA）is vital for constructing a robust xylose fermentation strain. In addition，the deletion of GRE3，strengthening of xylose transport and rational modification of xylose metabolic pathway during the metabolic modification of strain XI effectively improved the xylose fermentation capacity of the recombinant strains. Besides，evolutionary engineering also increased the xylose fermentation efficiency of XI strains. Furthermore，the omics technologies have presented their power in explaining the mechanism and developing the modification strategies of xylose metabolism. This paper reviews the research progresses on the expressions of xylose isomerase pathway in S. cerevisiae and analyzes the issues in the relevant studies. Reference | Related Articles | Metrics Select Research Progress on Substrate Species Degraded by Laccase ZHANG Ze-xiong, LIU Hong-yan, XING He, MA Yu Biotechnology Bulletin    2017, 33 (10): 97-102.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0417 Abstract （433）   HTML    PDF（pc） （1424KB）（562）       Knowledge map    Save Laccase，a polyphenol oxidase that binds multiple copper ions，is widely found in plants and fungi. Laccase contains unique copper ions which function is to transfer electrons in the structure，so that the laccase has a strong redox capacity，and the only product of the most reactions with lignin，amine compounds，aromatic compounds such as the role of the substrate is water. It has the characteristics of high efficiency and low cost in the degradation of many toxic substances and harmful pollutants，such as white rot fungi produced by the high level of laccase has been widely used in industrial wastewater treatment and other biological remediation and repair areas. In recent years，the lastest research showed that the using of vector immobilized enzyme technology allows laccase to be recycled after use and reused and more stable，which reduces costs while maintains the characteristics of laccase catalytic oxidation，it has overcome the problems of laccases in solving environmental pollution，Under the mediating effect of mediator，the problem of low potential of laccase redox has been figured out，and it greatly increased more kinds of substrate. Therefore，the application prospects in wastewater，degradation，soil remediation，industrial bleaching and other fields will be much broader. This paper summarily describes the applications of laccase in various fields and the types of harmful pollutions substrates，put forward the deficiency and the improving direction of existing degradation process of laccase aiming at providing the reference for the study of biodegradation of environmental pollutants. Reference | Related Articles | Metrics Select Research Advance on Remediation Technology of Cadmium Contaminated Soil GAO Yu, CHENG Qian , ZHANG Meng-jun , ZHU Zhen-yu , HU Ting-ting, YANG Yu Biotechnology Bulletin    2017, 33 (10): 103-110.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0336 Abstract （262）   HTML    PDF（pc） （1600KB）（1284）       Knowledge map    Save Cadmium（Cd）is a strongly toxic heavy metal that can be easily absorbed by plants and accumulated in human body through food chains so that result in health problems. Due to the increasingly wide use of cadmium and its compounds，there come more and more heavy-metal contaminated soil and other environmental problems，therefore the technologies of preventing and remedying cadmium-contaminated soil have attracted much attentions of many researchers in several fields. In this review，we introduce frequently-used remediation technologies in recent years，such as electrochemical-remediation，bioremediation，and so on，and followed a discussion about the mechanisms，applications，advantages and shortcomings of these remediation technologies. Moreover，we prospecte the future development trend of heavy-metal remediation technology，aiming at providing theory supports for the research and development of heavy metal repair. Reference | Related Articles | Metrics Select Strategies for Evaluating the Effects of Transgenic Crops on Soil Microbial Diversity LIANG Jin-gang, ZHANG Xiu-jie Biotechnology Bulletin    2017, 33 (10): 111-116.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0491 Abstract （244）   HTML    PDF（pc） （1449KB）（350）       Knowledge map    Save Microorganisms are the important components of the soil ecosystem. Soil microbial diversity is crucial to the maintenance of ecosystem functioning as soil microorganisms influence many ecosystem processes and drive biogeochemical cycles. Thus，it becomes a hot topic about the potential risks of transgenic crops to soil microorganisms and their effects on soil ecosystem. With the development of modern biotechnologies，the analysis methods for soil microbial diversity have been developed from the traditional separation culture to study microorganisms in the whole soil microecosystem. However，due to the various characteristics of soil microorganisms（such as majority being non-cultivable，tiny bulk，community quorum sensing，etc.）and the detection limitations of instruments and equipment，there are some disadvantages while only using single research method，and other methods should be combined to study microbial diversity in soil ecosystem. So far，the study on soil microbial diversity mainly includes species diversity，functional diversity，structural diversity and genetic diversity，there are a lot of methods used to study the effects of transgenic crops on the diversity of soil microorganisms. In this review，we summarize these methods，and finally the strategies for the future study are proposed. Reference | Related Articles | Metrics Select Application Analysis of Microcystis aeruginosa Identification Based on Ribosomal Proteins JIANG Wen-jing, ZHANG Jun-yi, DU Yang, SUN Li-wei Biotechnology Bulletin    2017, 33 (10): 117-124.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0268 Abstract （187）   HTML    PDF（pc） （2565KB）（200）       Knowledge map    Save This research is to verify the feasibility of matrix-assisted laser desorption-ionization-time-of -flight mass spectrometry（MALDI-TOF MS）in the identification of mixed and actual cyanobacterial samples by employing ribosomal proteins as biomarkers. Mechanical disruption and high speed centrifugation were used as pre-treatments to collect the ribosomal protein fraction of cyanobacterial samples，and then MALDI-TOF MS was applied to identify Microcystis aeruginosa in samples after proteins in situ crystallization with proteomic analysis based on 13 ribosomal proteins as biomarkers. The results showed that under the optimal conditions，model strain M. aeruginosa was precisely identified in the mixed samples and the detection rates of assigned peaks were all greater than 75% with reasonable errors range except the fourth sample. The lowest biomass detection limit and ratio of M. aeruginosa was 2.88×106 cells and 37%，respectively. Furthermore，M. aeruginosa was identified and detected in the cyanobacterial samples from Taihu Lake and the detection rate of assigned peaks was 76.9%. In conclusion，MALDI-TOF MS employing ribosomal proteins as biomarkers could be successfully applied to the identification of mixed and actual cyanobacterial samples and will be expected as routine tool in environmental cyanobacteria monitoring. Reference | Related Articles | Metrics Select Screening，Identification of Multifunctional Peanut Root-promoting Rhizobacteria and Its Promoting Effects on Peanuts（Arachis hypogaea L.） LIU Ye, LIU Xiao-dan, ZHANG Lin-li, WU Yue, WANG Guo-wen, WANG iang, JIANG Ying Biotechnology Bulletin    2017, 33 (10): 125-134.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0233 Abstract （241）   HTML    PDF（pc） （3625KB）（364）       Knowledge map    Save This study aims to acquire the peanut root-promoting rhizobacteria（PGPR）with multifunction of fixing nitrogen，dissolving phosphorus and potassium，and synthesizing the auxin，for increasing and improving the yield and quality of peanuts in Henan. Five PGPR strains of HS4，HS7，HS9，HS10，and HS11 were screened from sandy alluvial soil of peanut rhizosphere in North China. Further HS9 was chosen by comparing various functional indexes. The activity of nitrogenase，dissolving phosphorus and potassium and IAA synthesis of HS9 were 15.53 nmol C2H4/h·mL，279.23 mg/L，and 22.5 mg/L and 40.96 mg/L， respectively. HS9 was identified as Bacillus flexus based on the morphological observation，16S rDNA gene sequence analysis accompanied with physiological and biochemical test. Pot experiment was then conducted to test and verify the effects of growth promoting，and the results showed that inoculation with HS9 significantly increased the content of available phosphorus and potassium in soil，and distinctly enhanced the content of IAA in soil. This led to the root length，surface area，root volumes and root tips of peanut increased 109.60%，84.30%，76.08% and 386.24%，respectively. It indicated that the strain promoted plant nutrient uptake and utilization，and increased plant biomass and nutrient content. The average wet weight of plants was 1.7 times higher than the control treatment and the height of peanut inoculated with HS9 significantly increased by 28.35%；the SPAD（Soil and plant analyzer Development）value significantly increased by 16.06% and the total N，P and K content of peanut significantly increased by 23.11%、83.04% and 23.95%，respectively. Conclusively，the multifunctional strain HS9 has solid growth-promoting effect on peanut and broad agricultural application prospect. Reference | Related Articles | Metrics Select Screen of Poly-γ-gamma Glutamic Acid Producing Bacteria and Their Glutamic Acid Fermentation Broth’s Function on the Drought Resistance of Maize JIA Yan-ping, YIN Ai-ming, SUN Yan-mei, CHENG Shou-tao, WANG Xu-ming Biotechnology Bulletin    2017, 33 (10): 135-142.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0699 Abstract （219）   HTML    PDF（pc） （3412KB）（437）       Knowledge map    Save As a novel biological water absorbent，poly-γ-gamma glutamic acid（γ-PGA）has a significant application value on water-saving agricultural production. Two γ-PGA-producing strains，Y2 and P1，were isolated and screened from natto and fermented soya bean samples. By analyzing their morphological and physic-chemical characters，and 16S rRNA sequence，they were identified as Bacillus subtilis. Then，the effects of γ-PGA fermentation broth on the soil water-holding capacity and the drought resistance of maize seedling under water stress were also studied. The results showed that the fermentation broth of Y2 and P1 significantly decreased the soil water evaporation. Compared with the control treatment，adding fermentation broth from γ-PGA-producing strain promoted the soil water content by 4%. At the same time，the addition of γ-PGA fermentation broth enhanced the drought resistance of maize seedlings，and significantly increased aboveground and underground biomass of maize seedlings by 40.70% and 19.59%，respectively. The result of biologECO showed that the γ-PGA fermentation broth from Y2 and P1 had insignificant effect on microbial diversity and evenness. Thus，the γ-PGA fermentation broth is an environmental friendly biological water absorbent，which can be used directly to enhance soil water retention and drought resistance of vegetation in field. Reference | Related Articles | Metrics Select Isolation，Identification and Degrading Properties of Phlorizin-Degrading Fungi LIU Shu-yan, WANG Fang, WANG Jian-yu, LIN Rong-shan Biotechnology Bulletin    2017, 33 (10): 143-147.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0536 Abstract （228）   HTML    PDF（pc） （2665KB）（396）       Knowledge map    Save Screening highly efficient phlorizin-degrading microorganism is important for bioremediation of phlorizin-contaminated environment. This study aimed to isolate and identify high efficient phlorizin-degrading microorganism from the rhizosphere soils of apple，then to characterize degrading properties of target strains. Phlorizin-degrading microorganism were screened by the plate-culture method，used phloridzin as the sole carbon sources，and then the target strains were identified by the morphological and molecular methods. Degrading properties of phlorizin -degrading microorganism were determined under different condition of culture. The results showed that a phlorizin-degrading fungal strain AMCC300100 identified as Aspergillus terreus were obtained from the rhizosphere soils of apple replantd and non-replanted orchards surrounding Bohai gulf area. The phlorizin degradation rate of the strain AMCC300100 has reached 88.96%（phlorizin initial concentration of 2 mmol/L，pH5.0，2% inoculum）cultured 96h under the conditions of 40℃，160r/min；The strain AMCC300110 have high-efficient degradation ability not only for phlorizim but also for the other phenolic acids. Though plate-culture method，We obtained a fungal strain identified as Aspergillus terreus，this fungal strain have high-efficient degradation ability for phlorizim，and have tremendous potential in solving apple replant disease. Reference | Related Articles | Metrics Select Screening of Multi-functional Nitrogen Fixing Bacteria and Their Application in Soil Ecological Restoration MAO Xiao-jie, WANG Xin-min, ZHAO Ying, ZHOU Yi-qing, SUN Jian-guang Biotechnology Bulletin    2017, 33 (10): 148-155.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0678 Abstract （280）   HTML    PDF（pc） （1856KB）（620）       Knowledge map    Save The objective of this study is to screen multi-functional nitrogen-fixing bacteria based on nitrogenase and ACC（1-aminocyclopropane-1-carboxylate）deaminase activity，to develop inoculant and test its effect in wasteland soil ecological restoration. First，nitrogenase activity was determined by acetylene reduction assay，and ACC deaminase activity was quantitatively measured by colorimetry. Then，the 16S rRNA of the strains was amplified by PCR，and the phylogenetic status of the strains was investigated by sequence analysis and alignment. The identification of strains was carried out based on the morphology，physiology，biochemical test results，and 16S rRNA analysis. As results，total 47 strains with nitrogenase activity higher than 9 nmol C2H4/（h · mg）protein were screened，and the nitrogenase activities of the 43 strains were higher than that of positive control Azotobacter ACCC11103. And 20 strains producing ACC deaminase of 0.326 μmol/（h·mg）to 21.980 μmol/（h·mg）were obtained. Plant growth promotion test showed that the 47 strains increased the fresh weights of Chinese cabbage（Brassica campestris）. Based on 16S rRNA sequence，the 51 selected strains were identified as Agrobacterium albertimagni，Arthrobacter pascens，Bacillus circulans，Burkholderia vietnamiensis，Chitinophaga ginsengisegetis，Dyadobacter fermentans，Ensifer adhaerens，Enterobacter aerogenes，Lysobacter yangpyeongensis，Micrococcus luteus，Paenibacillus alginolyticus，Phyllobacterium ifriqiyense，Pseudomonas fluorescens，Rhizobium alamii，Sinorhizobium adhaerens，Sporolactobacillus laevolacticus of 31 species of 16 genera. After test，4 excellent strains of 7012，7134，7144，and 7164 were manufactured as inoculant termed as NFMF（Nitrogen Fixing and Multi Function）biofertilizer，with which the field experiment showed that soil microorganism quantity increased significantly after 3 months of NFMF biofertilizer inoculation，and soil activities of sucrase，catalase，urease，phosphatase，cellulase and xylanase significantly increased compared with the no inoculation control. In conclusion，NFMF can significantly increase wasteland soil bioactivity and it is valuable in the ecological restoration of wasteland soil. Reference | Related Articles | Metrics Select Isolation and Identification of a Zinc-resistant Strain and Effect of Its Characteristics on the Remediation Efficiency of Brassica juncea in Zinc-polluted Soil CHEN Yang, SONG Tian-shun, ZHOU Guo-ling, XIE Jing-jing Biotechnology Bulletin    2017, 33 (10): 156-162.   DOI: 10.13560/j.cnki.biotech.bull.1985.2017-0587 Abstract （193）   HTML    PDF（pc） （4109KB）（237）       Knowledge map    Save A zinc-resistant strain was isolated from heavy metal-polluted soil，and identified as Bacillus. Its performance of removing Zn2+ under different experimental conditions was studied. The results showed that：the removal efficiency of Zn2+ was the best，and the removal rate of Zn2+ was 94% in 12 h when the initial concentration of Zn2+ was 300 mg/L，the temperature was 37℃，inoculation amount was 5%. Subsequently，a pot experiment was conducted for investigating the influence of adding the different concentration of the strain on plant growth and Zn uptake by Brassica juncea. The results showed that the Zn content in ground and underground part of B. juncea increased by 56.1% and 24.3% respectively while adding 40 mL bacterial liquid（1×109 CFU/mL），compared with the control group. This is mainly due to the strain improves the zinc content under weak acid extraction condition. Reference | Related Articles | Metrics page Page 1 of 10 Total 382 records First page Prev page Next page Last page