TraM is required for quorum dependence. It binds to and in-activates TraR which controls the replication of the tumour-inducing virulence plasmid. TraM interacts in a two-step process with DNA-TraR to form a large, stable anti-activation complex [1,2].

1: Molecular basis of transcriptional antiactivation. TraM disrupts the TraR-DNA complex through stepwise interactions. Qin Y, Su S, Farrand SK; J Biol Chem. 2007;282:19979-19991. PMID:17475619

2: Quorum-sensing antiactivator TraM forms a dimer that dissociates to inhibit TraR. Chen G, Malenkos JW, Cha MR, Fuqua C, Chen L; Mol Microbiol. 2004;52:1641-1651. PMID:15186414