title: A Crp-dependent two-component system regulates nitrate and nitrite respiration in Shewanella oneidensis.
abstract: We have previously illustrated the nitrate/nitrite respiratory pathway of Shewanella oneidensis, which is renowned for its remarkable versatility in respiration. Here we investigated the systems regulating the pathway with a reliable approach which enables characterization of mutants impaired in nitrate/nitrite respiration by guaranteeing biomass. The S. oneidensis genome encodes an Escherichia coli NarQ/NarX homolog SO3981 and two E. coli NarP/NarL homologs SO1860 and SO3982. Results of physiological characterization and mutational analyses demonstrated that S. oneidensis possesses a single two-component system (TCS) for regulation of nitrate/nitrite respiration, consisting of the sensor kinase SO3981(NarQ) and the response regulator SO3982(NarP). The TCS directly controls the transcription of nap and nrfA (genes encoding nitrate and nitrite reductases, respectively) but regulates the former less tightly than the latter. Additionally, phosphorylation at residue 57 of SO3982 is essential for its DNA-binding capacity. At the global control level, Crp is found to regulate expression of narQP as well as nap and nrfA. In contrast to NarP-NarQ, Crp is more essential for nap rather than nrfA.
authors.affiliation: Institute of Microbiology and College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Yangyang
authors.initials: Y
authors.lastname: Dong
authors.forename: Jixuan
authors.initials: J
authors.lastname: Wang
authors.forename: Huihui
authors.initials: H
authors.lastname: Fu
authors.forename: Guangqi
authors.initials: G
authors.lastname: Zhou
authors.forename: Miaomiao
authors.initials: M
authors.lastname: Shi
authors.forename: Haichun
authors.initials: H
authors.lastname: Gao
mesh_terms: D002373:Cyclic AMP Receptor Protein / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology; D009565:Nitrate Reductases / Q000235:genetics; D009566:Nitrates / Q000378:metabolism; D009572:Nitrite Reductases / Q000235:genetics; D009573:Nitrites / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics / Q000502:physiology; D012119:Respiration / Q000235:genetics*; D017385:Sequence Homology; D020592:Shewanella / Q000235:genetics / Q000502:physiology
chemical_list: D002373:Cyclic AMP Receptor Protein; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D009566:Nitrates; D009573:Nitrites; D010750:Phosphoproteins; C481662:crp protein, E coli; C081466:narP protein, E coli; C088708:narQ protein, E coli; D009565:Nitrate Reductases; D009572:Nitrite Reductases