生物技术通报 ›› 2022, Vol. 38 ›› Issue (2): 113-122.doi: 10.13560/j.cnki.biotech.bull.1985.2021-0243

• 研究报告 • 上一篇    下一篇

烟嘧磺隆降解菌Chryseobacterium sp. LAM-M5的分离、鉴定及其降解机理研究

马青云1,2(), 江旭1, 李情情1,2, 宋金龙3, 周义清1, 阮志勇1,4,5()   

  1. 1.中国农业科学院农业资源与农业区划研究所/CAAS-CIAT可持续农业联合实验室,北京100081
    2.中国农业科学院研究生院,北京100081
    3.中国水产科学研究院,北京 100141
    4.西藏农牧学院资源与环境学院,林芝 860000
    5.烟台大学生命科学学院,烟台 264005
  • 收稿日期:2021-03-03 出版日期:2022-02-26 发布日期:2022-03-09
  • 作者简介:马青云,女,硕士,研究方向:环境微生物;E-mail: 1065178170@qq.com
  • 基金资助:
    国家自然科学基金项目(31670006);中央级科研院所基本科研业务费专项(1610132020009)

Isolation and Identification of Nicosulfuron Degrading Strain Chryseobacterium sp. LAM-M5 and Study on Its Degradation Pathway

MA Qing-yun1,2(), JIANG Xu1, LI Qing-qing1,2, SONG Jin-long3, ZHOU Yi-qing1, RUAN Zhi-yong1,4,5()   

  1. 1. CAAS-CIAT Joint Laboratory in Advanced Technologies for Sustainable Agriculture,Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081
    2. Graduate School of Chinese Academy of Agricultural Sciences,Beijing 100081
    3. Chinese Academy of Fishery Sciences,Beijing 100141
    4. College of Resources and Environment,Tibet Agricultural and Animal Husbandry University,Linzhi 860000
    5. College of Life Sciences,Yantai University,Yantai 264005
  • Received:2021-03-03 Published:2022-02-26 Online:2022-03-09

摘要:

为获得更丰富的烟嘧磺隆降解菌资源,以合肥某烟嘧磺隆生产厂活性污泥为研究对象,从中分离并筛选得到一株能以葡萄糖为唯一碳源、烟嘧磺隆为唯一氮源生长的菌株,根据其表型特征、16S rRNA序列相似性、DNA-DNA杂交值(DDH)和平均核苷酸一致性(ANI)的分析结果,将其鉴定为Chryseobacterium lacus LAM-M5。该菌株可在7 d内将初始浓度为50 mg/L的烟嘧磺隆降解92.39%。利用液相色谱-质谱联用(LC-MS)对菌株LAM-M5与烟嘧磺隆混合培养后的代谢产物进行检测与鉴定,共有5种主要物质被检测到,根据烟嘧磺隆的化学结构式和中间代谢产物特征,初步推测出菌株Chryseobacterium sp. LAM-M5降解烟嘧磺隆的可能降解途径。利用高效液相色谱(HPLC)对接菌后降解体系内代谢产生的酸类物质进行分离与鉴定,结果表明产物主要为L-苹果酸。推测菌株LAM-M5受高浓度烟嘧磺隆胁迫,利用葡萄糖产生L-苹果酸,通过降低环境 pH使烟嘧磺隆发生水解,从而解除其胁迫。通过对菌株全基因组信息进行分析,预测了7种可能与烟嘧磺隆降解相关的基因。结果表明,菌株LAM-M5 具有较强的烟嘧磺隆降解能力,在烟嘧磺隆污染环境的生物修复上具有较好的应用潜力。

关键词: 烟嘧磺隆, 金黄杆菌属, 微生物降解, 代谢途径

Abstract:

In order to obtain more nicosulfuron-degrading bacterial resources,the activated sludge samples from a nicosulfuron manufacturer in Hefei city were used for study object,from which an isolated and screened strain grew well with glucose as sole carbon source and nicosulfuron as sole nitrogen source. Based on its phenotypic characteristics,the 16S rRNA gene sequence similarity,the values of DNA-DNA hybridization and average nucleotide identity,it was identified as Chryseobacterium lacus LAM-M5. This strain degraded 92.39% of 50 mg/L nicosulfuron within 7 d. Liquid chromatography mass spectrometry was used to detect and identify the metabolites after mixing culture of LAM-M5 and nicosulfuron,and 5 major substances were detected. The metabolic pathway of LAM-M5 degrading nicosulfuron was primarily speculated based on the chemical structure and characteristics of intermediates. High performance liquid chromatography was employed to isolate and identify the acids generated during the degradation of nicosulfuron by strain LAM-M5,and the results showed that L-malic acid was predominant. It was deduced that strain LAM-M5 metabolized the glucose into L-malic acid when its growth was stressed by the nicosulfuron,from which the environmental pH decreased and the nicosulfuron hydrolyzed,thus the stress was released. Through the analysis of the whole genome sequence of strain LAM-M5,7 annotated genes that may contribute to the degradation of nicosulfuron were predicted. The results reveal that strain LAM-M5 has excellent ability of degrading nicosulfuron and may have promising application potential in the microbial remediation of nicosulfuron -polluted environment.

Key words: nicosulfuron, Chrysobacterium, microbial degradation, metabolic pathway