生物技术通报 ›› 2017, Vol. 33 ›› Issue (6): 81-88.doi: 10.13560/j.cnki.biotech.bull.1985.2016-1208

• 研究报告 • 上一篇    下一篇

甲基戊糖梭菌膜整合焦磷酸酶提高转基因烟草的抗旱性

刘延娟, 杨玉梅, 刘娴, 高艳秀, 袁航, 龚明, 邹竹荣   

  1. 云南师范大学生命科学学院 云南省生物质能源和环境生物技术重点实验室 教育部生物质能源持续发展和应用工程研究中心,昆明 650500
  • 收稿日期:2017-01-09 出版日期:2017-06-26 发布日期:2017-06-19
  • 作者简介:刘延娟,女,硕士研究生,研究方向:植物逆境生物学;E-mail:2271937509@qq.com
  • 基金资助:
    国家自然科学基金项目(31160169,31460067)

Membrane-bound Pyrophosphatase of Clostridium methylpentosum Increases the Drought Resistance of Its Transgenic Tobacco

LIU Yan-juan, YANG Yu-mei, LIU Xian, GAO Yan-xiu, YUAN Hang, GONG Ming, ZOU Zhu-rong   

  1. Engineering Research Center of Sustainable Development and Utilization of Biomass Energy,Ministry of Education; Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province; School of Life Sciences,Yunnan Normal University,Kunming 650500
  • Received:2017-01-09 Published:2017-06-26 Online:2017-06-19

摘要: 由焦磷酸(PPi)驱动的膜整合焦磷酸酶(PPase)在生物适应逆境方面可能起着重要作用,包括H+-PPase、Na+-PPase和Na+,H+-PPase三个亚家族。相比于H+-PPase,其它两个亚家族PPase近年来才在原核生物(特别是动物肠道菌)中被发现,有关它们的应用研究更是匮乏。通过两轮巢式PCR从人肠道宏基因组中扩增得到甲基戊糖梭菌膜整合焦磷酸酶(CmPP)全长基因。序列分析表明该基因含有一个完整的ORF(长2 100 bp,编码一个699 aa的蛋白质,G+C含量为59.9 %,碱基分布均衡)。膜拓扑学结构预测CmPP是一个由16个跨膜α螺旋组成的膜蛋白,与目前已鉴定过的膜PPase跨膜结构相符。序列比对分析推测CmPP属于K+依赖型Na+,H+-PPase亚家族成员。另外,通过农杆菌转化获得了CmPP转基因烟草。对其子一代植株的抗旱分析发现,在干旱胁迫条件下CmPP转基因株系的干物质含量、总叶绿素含量和根系活力均下降,而其叶片MDA含量和电解质渗透率均升高,但相同胁迫下的变化程度都显著低于野生型烟草。这些结果表明CmPP基因的导入能够有效提高烟草的抗旱能力。

关键词: 甲基戊糖梭菌, 膜整合焦磷酸酶, 基因克隆, 转基因烟草, 抗旱性

Abstract: Pyrophosphate(PPi)-energized membrane-bound pyrophosphatases(PPases)are composed of three subfamilies including H+-PPase,Na+-PPase and Na+,H+-PPase,and may play important roles in stress adaptation of organisms. In contrast to H+-PPase,other two PPase subfamilies were recently detected only in prokaryotes(especially animal gut microbial),certainly with scarce application researches. In this study,through two rounds of nested PCR,we amplified the full-length gene of the membrane-bound PPase of Clostridium methylpentosum(CmPP)from human gut metagenome. As indicated by sequence analysis,the CmPP gene contained an entire ORF of 2100 bp encoding a protein of 699 aa,with the G+C percentage of 59.9 % and balanced base distribution. Topological prediction showed CmPP as a multi-spanning membrane protein consisting of 16 transmembrane α-helix segments,in accordance with the membrane topological model of those known membrane PPases. Furthermore,sequence alignment analysis implicated CmPP as a K+-dependent member of Na+,H+-PPase subfamily. In addition,we obtained the CmPP transgenic tobacco plants through Agrobacterium transformation. Under drought stress conditions,the F1 plants of CmPP transgenic lines had decreased values in dry matter content,total chlorophyll content and root activity,but increased values in leaf MDA content and electrolyte permeability. However,all these changes in transgenic lines were significantly lower than those in wild-type tobacco under the same stress. Conclusively,our results indicated that introduction of the CmPP gene efficiently improved the drought resistance in tobacco.

Key words: Clostridium methylpentosum, membrane-bound pyrophosphatase, gene cloning, transgenic tobacco, drought resistance