Gao Lang, Guo Zisheng, Wang Yue, Wang Yulu, Wang Kerong, Li Bo, Shen Lixin
Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, Faculty of Life Sciences, Northwest University, Xi'an, 710069, China.
J Membr Biol. 2018 Feb;251(1):91-104. doi: 10.1007/s00232-017-9979-5. Epub 2017 Oct 3.
Iron is essential for all organisms. Bacteria have devolved sophisticated systems to maintain intracellular iron homeostasis. FpvCDEF(PA2407-2410) has been reported as an ABC transporter involved in pyoverdine-Fe uptake which does not affect growth under iron-limiting condition, when it is deleted in PAO1. In this study, we proved that fpvCDEF and fpvWXYZ(PA2403-2406) constituted an ABC transporter complex containing two operons: fpvWXYZCDE and fpvF. The operon fpvWXYZCDE was regulated by iron negatively and the single gene operon fpvF was constitutively expressed. Inactivation of any one of the components, fpvW, fpvC, fpvD, fpvE, and fpvF, led to increased expression of fpvWXYZCDE suggesting that each component of fpvWXYZCDEF could be involved in iron uptake. The ABC transporter complex encoded by fpvWXYZCDEF plays important roles in growth, oxidative stress resistance, and virulence, since the deletion of fpvWXYZCDEF resulted in defective growth, increased sensitivity to HO, and decreased virulence compared with PAO1(ΔfpvCDEF) and the wild type PAO1 under iron-limiting condition.
铁对所有生物体都至关重要。细菌已经进化出复杂的系统来维持细胞内铁稳态。FpvCDEF(PA2407 - 2410)已被报道为一种参与绿脓菌素 - 铁摄取的ABC转运蛋白，在PAO1中缺失该蛋白时，在铁限制条件下不影响生长。在本研究中，我们证明了fpvCDEF和fpvWXYZ(PA2403 - 2406)构成了一个包含两个操纵子的ABC转运蛋白复合物：fpvWXYZCDE和fpvF。操纵子fpvWXYZCDE受铁的负调控，单基因操纵子fpvF组成型表达。fpvW、fpvC、fpvD、fpvE和fpvF中任何一个成分的失活都会导致fpvWXYZCDE表达增加，这表明fpvWXYZCDEF的每个成分都可能参与铁摄取。由fpvWXYZCDEF编码的ABC转运蛋白复合物在生长、抗氧化应激和毒力方面发挥重要作用，因为与PAO1(ΔfpvCDEF)和野生型PAO1相比，在铁限制条件下，fpvWXYZCDEF的缺失导致生长缺陷、对H₂O₂敏感性增加和毒力降低。
