title: The two-component regulators GacS and GacA positively regulate a nonfluorescent siderophore through the Gac/Rsm signaling cascade in high-siderophore-yielding Pseudomonas sp. strain HYS.
abstract: Siderophores, which are produced to overcome iron deficiency, are believed to be closely related to the adaptability of bacteria. The high-siderophore-yielding Pseudomonas sp. strain HYS simultaneously secretes the fluorescent siderophore pyoverdine and another nonfluorescent siderophore that is a major contributor to the high siderophore yield. Transposon mutagenesis revealed siderophore-related genes, including the two-component regulators GacS/GacA and a special cluster containing four open reading frames (the nfs cluster). Deletion mutations of these genes abolished nonfluorescent-siderophore production, and expression of the nfs cluster depended on gacA, indicating that gacS-gacA may control the nonfluorescent siderophore through regulation of the nfs cluster. Furthermore, regulation of the nonfluorescent siderophore by GacS/GacA involved the Gac/Rsm pathway. In contrast, inactivation of GacS/GacA led to upregulation of the fluorescent pyoverdine. The two siderophores were secreted under different iron conditions, probably because of differential effects of GacS/GacA. The global GacS/GacA regulatory system may control iron uptake by modulating siderophore production and may enable bacteria to adapt to changing iron environments.
authors: College of Life Sciences, Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), State Key Laboratory of Virology, Wuhan University, Wuhan, People's Republic of China Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Wuhan, People's Republic of China.
authors: Xinyan
authors: X
authors: Yu
authors: College of Life Sciences, Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), State Key Laboratory of Virology, Wuhan University, Wuhan, People's Republic of China Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Wuhan, People's Republic of China.
authors: Min
authors: M
authors: Chen
authors: College of Life Sciences, Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), State Key Laboratory of Virology, Wuhan University, Wuhan, People's Republic of China Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Wuhan, People's Republic of China.
authors: Zhen
authors: Z
authors: Jiang
authors: College of Life Sciences, Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), State Key Laboratory of Virology, Wuhan University, Wuhan, People's Republic of China.
authors: Yi
authors: Y
authors: Hu
authors: College of Life Sciences, Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), State Key Laboratory of Virology, Wuhan University, Wuhan, People's Republic of China Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Wuhan, People's Republic of China zxxie@whu.edu.cn.
authors: Zhixiong
authors: Z
authors: Xie
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D011549:Pseudomonas / Q000235:genetics / Q000378:metabolism*; D017262:Siderophores / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; C091100:GacA protein, Bacteria; D017262:Siderophores; D014157:Transcription Factors; C074165:lemA protein, bacterial