Salifi V, AMicosante G, Strom R
Ital J Biochem. 1977 Jan-Feb;26(1):37-43.
Buffer composition affects the pattern of inactivation of B. cereus beta-lactamase I by dicloxacillin. At pH 7.0, in the presence of phosphate ions, dicloxacillin appears to cause essentially an irreversible inactivation of the catalytic site of the enzyme, while in a tris-cacodylate buffer the inactivation process appears to affect essentially the substrate-binding site. Buffer ions act presumably by interacting themselves with either the catalytic or the substrate-binding site of the enzyme, thus modifying the affinity of these sites for the halogenated isoxazolyl-penicillins.
缓冲液组成会影响双氯西林对蜡样芽孢杆菌β-内酰胺酶I的失活模式。在pH 7.0、存在磷酸根离子的情况下，双氯西林似乎会导致该酶催化位点发生基本不可逆的失活，而在三羟甲基氨基甲烷-二甲胂酸盐缓冲液中，失活过程似乎主要影响底物结合位点。缓冲液离子可能通过自身与酶的催化位点或底物结合位点相互作用，从而改变这些位点对卤代异恶唑基青霉素的亲和力。
