Intracellular nuclease activities of buffalo rumen bacterial population

Nuclease activities of the predominantly bacterial population obtained from buffalo rumen were investigated. Optimum temperature for hydrolysis of both DNA and RNA was 50 degrees C whereas DNAase activity was observed to be stable up to 50 degrees C, a decrease in RNAase activity was observed even after 40 degrees C. Two pH optima, one at 5.5 and the other at 7.5, were recorded for hydrolysis of DNA. RNAase activity was maximum between pH 6.0 to 7.0. Whereas DNAase activity was stable near its optimum pH, RNAase activity was stable between pH 7.0 to 8.5. Mn2+ ions stimulated DNAase activity. It was strongly inhibited by Hg2+, Zn2+, Pb2+ and Ag+. RNAase activity was stimulated by Mg2+ ions and was strongly inhibited by Hg2+, Cu2+, Zn2+ and Ag+. Cysteine hydrochloride and 2-mercaptoethanol stimulated DNAase activity. The activity was strongly inhibited by N-ethylmaleimide, 4-chloromercuribenzoate, 8-quinolinol, iodoacetic acid and 1,10-phenanthroline. RNAase activity was stimulated by cysteine hydrochloride, reduced glutathione and 2-mercaptoethanol and was strongly inhibited by 4-chloromercuribenzoate, 8-quinolinol and 2,2'bipyridyl.