MOLECULAR-CLONING OF SHEEP LUNG DIPEPTIDASE - A GLYCOSYL PHOSPHATIDYLINOSITOL-ANCHORED ECTOENZYME THAT CONVERTS LEUKOTRIENE D-4 TO LEUKOTRIENE E(4)

Sheep lung dipeptidase was released from a plasma membrane preparation by digestion with a phosphatidylinositol-specific phospholipase C. Th e dipeptidase was purified to homogeneity using affinity chromatograph y followed by high performance liquid chromatography. The NH2-terminal sequence was determined and employed to prepare a probe to clone the c-DNA of the enzyme. The primary structure of sheep lung dipeptidase, deduced from the c-DNA exhibited a high homology to kidney dipeptidase s cloned from other animal species. Northern analysis detected the m-R NA of the dipeptidase in lung, kidney, and intestinal tissues of the s heep.