SecB modulates the nucleotide-bound state of SecA and stimulates ATPase activity

During the SecB stimulation of SecA ATPase activity, SecB interacts with SecA inducing a conformational change that favors ATP binding and hydrolysis. Data show that SecB-enhanced Seca ATPase activity is due to an increase in the ATP hydrolysis rate. Further, the conformation of the high-affinity nucleotide binding site is regulated by SecB.