FIG 7.

Proposed model for the QS/AbaM IFFL in A. baumannii 5075. AbaR activated by OHC12 positively activates expression of abaM and abaI and hence OHC12 production. AbaM is negatively autoregulated and also represses expression of both abaR and abaI. Under the growth conditions used here, AbaM negatively regulates surface motility, biofilm, and Csu pili but is required for virulence as abaM mutants are avirulent in Galleria mellonella larvae. Green arrows and red lines represent positive and negative regulation, respectively.