Abstract
Three ribonucleases (RNases) were partially purified from Trichoderma koningii by means of ammonium sulfate fractionation, column chromatographies on Amberlite IRC-50, Sephadex G-100, phospho-cellulose or diethylaminoethyl (DEAE)-cellulose and Sephadex G-75. Three RNases fractions, fraction I-III, are non-specific in respect of bases. Fraction I and II released nucleotides from ribonucleic acid (RNA) in the order of A>U>G>C and fraction III released nucleotides in the order of G>A>U>C. Molecular weight of three fractions estimated by gel filtration was 24000, 18000 and 6000, respectively. pH optimum of fractions I and II was at pH 4.3 and that of fraction III was at pH 4.8. Cu2+, Zn2+ and Hg2+ inhibited fractions I and II at the concentration of 10-3M, but fraction II moderately. Mg2+ had no effect on the enzymatic activity of fraction I and II, but it accelerated fraction III activity considerably.
