文章基本信息

标题：Site-directed mutagenesis of Campylobacter concisus respiratory genes provides insight into the pathogen’s growth requirements
本地全文：下载
作者：Stéphane L. Benoit ; Robert J. Maier
期刊名称：Scientific Reports
电子版ISSN：2045-2322
出版年度：2018
卷号：8
期号：1
页码：14203
DOI：10.1038/s41598-018-32509-9
语种：English
出版社：Springer Nature
摘要：Campylobacter concisus is an emerging human pathogen found throughout the entire human oral-gastrointestinal tract. The ability of C . concisus to colonize diverse niches of the human body indicates the pathogen is metabolically versatile. C . concisus is able to grow under both anaerobic conditions and microaerophilic conditions. Hydrogen (H₂) has been shown to enhance growth and may even be required. Analysis of several C . concisus genome sequences reveals the presence of two sets of genes encoding for distinct hydrogenases: a H₂-uptake-type (“Hyd”) complex and a H₂-evolving hydrogenase (“Hyf”). Whole cells hydrogenase assays indicate that the former (H₂-uptake) activity is predominant in C . concisus , with activity among the highest we have found for pathogenic bacteria. Attempts to generate site-directed chromosomal mutants were partially successful, as we could disrupt hyfB , but not hydB , suggesting that H₂-uptake, but not H₂-evolving activity, is an essential respiratory pathway in C . concisus . Furthermore, the tetrathionate reductase ttrA gene was inactivated in various C . concisus genomospecies. Addition of tetrathionate to the medium resulted in a ten-fold increase in cell yield for the WT, while it had no effect on the ttrA mutant growth. To our knowledge, this is the first report of mutants in C . concisus .