Functional analysis of hydrogenases and their effects on cell growth and magnetosome synthesis in Magnetospirillum gryphiswaldense  

作　　者：BAN Jia JIANG Wei LI Ying ZHANG YaoPing LI JiLun 

机构地区：[1]State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing 100193, China [2]Department of Bacteriology, University of Wisconsin-Madison, Madison, W153706, USA

出　　处：《Chinese Science Bulletin》2010年第13期1271-1277,共7页

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 30570023 and 30870043);National High Technol-ogy Research and Development Program of China (Grant No2007AA021805)

摘　　要：This study addressed the effect of hydrogen metabolism on cell growth and magnetosome synthesis in Magnetospirillum gryphiswaldense strain MSR-1. Two deletion mutants were generated: L206, with single deletion of the hupL gene encoding H2-uptake [NiFe] hydrogenase; and B206, with double deletion of the hyaB gene encoding H2-producing [NiFe] hydrogenase and the hupL gene. The wild-type and mutant strains were compared in terms of hydrogen uptake capability, hydrogen yield, growth rate, and iron uptake, and observed by transmission electron microscopy. Results indicate that HupSL protein is a specific H2-uptake hydrogenase while HyaAB protein is a specific H2-producing hydrogenase. In comparison to wild-type and B206, L206 released a greater quantity of H2 under conditions that induce magnetosomes synthesis, and showed higher rates of growth and iron uptake. M. gryphiswaldense appears to regulate reducing power in vivo, via H2-uptake hydrogenase and H2-producing hy- drogenase, to promote iron absorption and magnetosome synthesis.This study addressed the effect of hydrogen metabolism on cell growth and magnetosome synthesis in Magnetospirillum gryphiswaldense strain MSR-1. Two deletion mutants were generated： L206, with single deletion of the hupL gene encoding H2-uptake [NiFe] hydrogenase; and B206, with double deletion of the hyaB gene encoding H2-producing [NiFe] hydrogenase and the hupL gene. The wild-type and mutant strains were compared in terms of hydrogen uptake capability, hydrogen yield, growth rate, and iron uptake, and observed by transmission electron microscopy. Results indicate that HupSL protein is a specific H2-uptake hydrogenase while HyaAB protein is a specific H2-producing hydrogenase. In comparison to wild-type and B206, L206 released a greater quantity of H2 under conditions that induce magnetosomes synthesis, and showed higher rates of growth and iron uptake. M. gryphiswaldense appears to regulate reducing power in vivo, via H2-uptake hydrogenase and H2-producing hydrogenase, to promote iron absorption and magnetosome synthesis.

关 键 词：诱导合成 细胞生长 氢化酶 电子显微镜观察 氢气生产 螺 吸收能力 缺失突变体 

分 类 号：Q933[生物学—微生物学]