Purification and some properties of talopeptin (MK-I), a novel proteinase inhibitor produced by Streptomyces mozunensis MK-23.

Abstract

A novel proteinase inhibitor, talopeptin (MK-I), was found in the culture filtrate of Streptomyces mozunensis MK-23, which is a new species of the genus Streptomyces. Talopeptin was successively purified from the culture filtrate by carbon adsorption, butanol extraction, and DEAE-Sephadex A-25, carbon and Sephadex G-10 chromatographies. The structure was elucidated to be 6-deoxy-α-L-talopyranosyloxyphospho-L-leucyl-L-tryptophan as described previously.1) Talopeptin is stable in neutral or alkaline solutions, but unstable in an acidic solution. Inhibitory activity of talopeptin against thermolysin noticeably decreased at pHs higher than 7.