nicking response catalysed from the MobA89K and MobC89K proteins. The cleaved strand is then unwound via the helicase and sent to the 89K-encoded GI-form T4SS machinery. The VirB1-89K part is assumed to act as a lytic transglycosylase, regionally opening the peptidoglycan with contributions from Another component(s) in the assembly from the transpo