Isolation of a new lytic enzyme for hiochi bacteria and other lactic acid bacteria

A microorganism producing a lytic enzyme preparation that could rapidly lys e bacterial cells such as hiochi bacteria and other lactic acid bacteria wa s screened. The microorganism was identified as Streptomyces fulvissimus. T he enzyme produced by this organism lysed boil-denatured cells quicker than intact cells of hiochi bacteria. A mutant strain of S. fulvissimus produci ng the enzyme exhibiting high activity against intact cells of hiochi bacte ria was screened on plates, containing intact cells inactivated with UV irr adiation. The optimal pH for lytic activity against intact cells of the hio chi bacterium Lactobacillus casei S-4 was from 3.5 to 4.0, and the optimum temperature was close to 50 degreesC. This enzyme activity was stable betwe en pH 3.5 and pH 8.0 and up to 60 degreesC. The enzyme exhibits N-acetyl gl ucosaminidase and muramidase activities. The effects of adjusting the pH an d using different inducers for enzyme production were investigated. Chitin was the most effective inducer of enzyme production. Intact DNA was easily isolated from the cells of many lactic acid bacteria following lysis with t he enzyme. It is thought that this enzyme will be a good biotechnological t ool.