Abstract
New neutral proteinases, designated retikinonase I and II, have been isolated from the cultured broth of a Streptomyces strain. Both enzymes are purified by gradient column chromatography on DEAE-cellulose and gel filtration on a column of Sephadex G-75. Retikinonase I and II are of basic protein nature and contain the same constituent amino acids. Both enzymes have enzymatic characteristics similar to neutral proteinases of microbial origin and hydrolyze bradykinin by the same manner with kinonase AI, AIII or BI. Retikinonase I showed very high anti-inflammatory activity for carrageenininduced edema in the hind paw of rats, but retikinonase II did not show the significant activity. The retikinonase-producing strain is considered to be similar to Str. uerticillatus. Taxonomic studies of the producing organism, production, isolation, purification, pysicochemical properties, effect of pH on proteolytic activity, pH stability, effect of temperature on proteolytic activity, thermal stability, effect of inhibitors on proteolytic activity, andsubstrate specificities of retikinonase I and II are reported in this paper.
