Chitinase production by Streptomyces viridificans: its potential in fungal cell wall lysis.

Streptomyces viridificans was found to be a good chitinase producer among nine species of Streptomyces screened. Minimum levels of constitutive enzyme were observed with both simple and complex carbon substrate. Arabinose doubled the enzyme production amongst the various pentoses and hexoses used with chitin. However, with glucose end-product inhibition and catabolite repression were observed. The enzyme tolerated a wide range of temperature (30-55 degrees C) and pH (3-7.5). Among various divalent cations Mn2+ and Hg2+ completely inhibited the purified enzyme while beta-mercaptoethanol stimulated its activity. Crude and purified enzyme had potential for cell wall lysis of many fungal pathogens tested.