期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2010
卷号：107
期号：34
页码：15223-15228
DOI：10.1073/pnas.1007805107
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Siderophores are essential factors for iron (Fe) acquisition in bacteria during colonization and infection of eukaryotic hosts, which restrain iron access through iron-binding protein, such as lactoferrin and transferrin. The synthesis of siderophores by Escherichia coli is considered to be fully regulated at the transcriptional level by the Fe-responsive transcriptional repressor Fur. Here we characterized two different pathways that promote the production of the siderophore enterobactin via the action of the small RNA RyhB. First, RyhB is required for normal expression of an important enterobactin biosynthesis polycistron, entCEBAH. Second, RyhB directly represses the translation of cysE, which encodes a serine acetyltransferase that uses serine as a substrate for cysteine biosynthesis. Reduction of CysE activity by RyhB allows serine to be used as building blocks for enterobactin synthesis through the nonribosomal peptide synthesis pathway. Thus, RyhB plays an essential role in siderophore production and may modulate bacterial virulence through optimization of siderophore production.
