Peptidases of the kidney microvillus membrane.

The microvillus membrane of the kidney is highly differentiated in its complement of enzymes and other proteins. In addition to the five well documented peptidases that are present in the membrane, recent work suggests that aminopeptidase P, carboxypeptidase P and an enzyme tentatively referred to as "leucine hydrazidase" are also microvillus enzymes. Microvillus serine peptidase (dipeptidyl peptidase IV) has been purified after detergent solubilization. The catalytic and molecular properties of this form and the form released by autolysis have been compared in an attempt to gain understanding of the intramembranous domain of this protein. Current views on the molecular organization of the microvillus are discussed.