Linked Life Data

19387485

Source:http://linkedlifedata.com/resource/pubmed/id/19387485

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2009-7-21
pubmed:abstractText
In the genome of Shewanella oneidensis, a napDAGHB gene cluster encoding periplasmic nitrate reductase (NapA) and accessory proteins and an nrfA gene encoding periplasmic nitrite reductase (NrfA) have been identified. These two systems seem to be atypical because the genome lacks genes encoding cytoplasmic membrane electron transport proteins, NapC for NAP and NrfBCD/NrfH for NRF, respectively. Here, we present evidence that reduction of nitrate to ammonium in S. oneidensis is carried out by these atypical systems in a two-step manner. Transcriptional and mutational analyses suggest that CymA, a cytoplasmic membrane electron transport protein, is likely to be the functional replacement of both NapC and NrfH in S. oneidensis. Surprisingly, a strain devoid of napB encoding the small subunit of nitrate reductase exhibited the maximum cell density sooner than the wild type. Further characterization of this strain showed that nitrite was not detected as a free intermediate in its culture and NapB provides a fitness gain for S. oneidensis to compete for nitrate in the environments. On the basis results from mutational analyses of napA, napB, nrfA and napBnrfA in-frame deletion mutants, we propose that NapB is able to favor nitrate reduction by routing electrons to NapA exclusively.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1751-7370
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
966-76
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Reduction of nitrate in Shewanella oneidensis depends on atypical NAP and NRF systems with NapB as a preferred electron transport protein from CymA to NapA.
pubmed:affiliation
College of Life Sciences and Institute of Microbiology, Zhejiang University, Hangzhou, Zhejiang, China. haichung@zju.edu.cn
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't