... sites 1 and 2 and involved in bind-ing of adenylic nucleotides and BPG.Our results partially confirm the molecular model-ling, suggesting that effector site 1 is the binding sitefor Ap4A and ... S2), and, in particular, a modification in the interaction of this resi-due with Asp351 (directly involved in Mg2+binding) and His352 both belonging to motif III. Remarkably,mutant D396A, in ... amino acidsat interface A (Phe36, Tyr115 and Asp396) and two atinterface B (Lys311 and Gly319).Interface A In the model proposed on the basis of the crystal struc-ture, interface A is involved...