<p>It is intended to provide an actinomyces-origin neutral metalloprotease, which selectively cleaves the pro-structure moiety of a microorganism-origin protransglutaminase, and a gene encoding the same. An activated microorganism-origin transglutaminase from which the pro-structural moiety has been excised can be produced by culturing a microorganism having the gene encoding the above-described actinomyces-origin neutral metalloprotease transferred thereinto, allowing the microorganism to produce the actinomyces-origin neutral metalloprotease and then treating the microorganism-origin protransglutaminase therewith.</p>
