Structure of a kallikrein-like enzyme and its tissue localization in the dog

We previously purified a kallikrein-like enzyme from the dog heart and demo nstrated that it is not only able to form kinins but can also convert angio tensin (Ang) I to Ang II. The aim of the present study was to clarify the s tructure and tissue localization of this enzyme. Western blot analysis of v arious canine tissues was performed with antiserum against the purified dog heart enzyme. The purified enzyme was subjected to a determination of its amino acid composition and a sequence analysis. Western blotting indicated that this enzyme was present in the heart, aorta, kidney, pancreas, lung, L iver, spleen, small intestine, and skeletal muscle. The amino acid composit ion of the enzyme was different from that of dog urinary kallikrein. Amino acid sequence analysis indicated that it is likely to be N-terminally block ed. The present study showed that this kallikrein-like enzyme is different from previously reported kallikrein and is distributed not only in the hear t, but also in other tissues such as the aorta, kidney, lung, liver, spleen , small intestine, and skeletal muscle. This enzyme may exert local effects by generating kinins and Ang II. (C) 1999 Elsevier Science B.V. All rights reserved.