HMM Summary Page: TIGR02739

Functiontype-F conjugative transfer system pilin assembly protein TraF
Gene SymboltraF
Trusted Cutoff204.60
Domain Trusted Cutoff204.60
Noise Cutoff183.65
Domain Noise Cutoff183.65
Isology Typeequivalog
HMM Length256
AuthorSelengut J
Entry DateDec 18 2005 9:48AM
Last ModifiedFeb 14 2011 3:27PM
CommentThis protein is part of a large group of proteins involved in conjugative transfer of plasmid DNA, specifically the F-type system. This protein has been predicted to contain a thioredoxin fold and has been shown to be localized to the periplasm [1]. Unlike the related protein TrbB (TIGR02738), TraF does not contain a conserved pair of cysteines and has been shown not to function as a thiol disulfide isomerase by complementation of an Ecoli DsbA defect [2]. The protein is believed to be involved in pilin assembly [3]. Even more closely related than TrbB is a clade of genes (TIGR02740) which do contain the CXXC motif, but it is unclear whether these genes are involved in type-F conjugation systems per se.
ReferencesRN [1] RM PMID: 3042757 RA Wu JH, Kathir P, Ippen-Ihler K RT The product of the F plasmid transfer operon gene, traF, is a periplasmic protein RL J Bacteriol. 1988 Aug;170(8):3633-9. RN [2] RM PMID: 16321931 RA Elton TC, Holland SJ, Frost LS, Hazes B. RT F-like type IV secretion systems encode proteins with thioredoxin folds that are putative DsbC homologues. RL J Bacteriol. 2005 Dec;187(24):8267-77. RN [3] RM PMID: 16138100 RA Frost LS, Leplae R, Summers AO, Toussaint A. RT Mobile genetic elements: the agents of open source evolution. RL Nat Rev Microbiol. 2005 Sep;3(9):722-32.
Genome PropertyGenProp0484: F-type conjugation system (type IV secretion) specific components (HMM)