TraQ is a conjugative transposon lipoprotein. It is a component of the type IV secretion system. TraQ belongs to the immunoglobulin superfamily and shares structural similarity to other proteins involved in pili production for bacterial cell attachment [3]. It appears to be upregulated in the presence of host or other bacterial species vs when in culture [1,2].

1: Glycan foraging in vivo by an intestine-adapted bacterial symbiont. Sonnenburg JL, Xu J, Leip DD, Chen CH et al Science 2005 Mar 25;307(5717):1955-9. PMID:15790854

2: A hybrid two-component system protein of a prominent human gut symbiont couples glycan sensing in vivo to carbohydrate metabolism. Sonnenburg ED, Sonnenburg JL, Manchester JK, Hansen EE et al. Proc Natl Acad Sci U S A 2006 Jun 6;103(23):8834-9. PMID:16735464

3: Solution NMR structure of BT_0084, a conjugative transposon lipoprotein from Bacteroides thetaiotamicron. Ramelot TA, Yang Y, Xiao R, Acton TB, Everett JK, Montelione GT, Kennedy MA; Proteins. 2012;80:667-670. PMID:22116783