title: Purification and properties of two ribonucleases and a nuclease from barley seeds.
abstract: Three enzymes possessing RNAase activity were isolated from barley seeds. These enzymes were further purified by ammonium sulphate precipitation DEAE-cellulose chromatography, gel filtration on Sephadex G-75 and DEAE-Sephadex A-50 chromatography. These enzymes have been characterized and classified as: 1. Plant RNAase I (EC 3.1.27.1). It has a pH optimum at 5.7 and molecular weight of 19 000. 2. Plant RNAase II (EC 3.1.27.1). It has a pH optimum at 6.35 and molecular weight of 19 000. 3. Plant nuclease I (EC 3.1.30.2). It has a pH optimum at 6.8 and molecular weight of 37 000. Two RNAases were purified to homogeneity by means of affinity chromatography on poly(G)-Sepharose 4B, as shown by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate.
mesh_terms: D004591:Electrophoresis, Polyacrylamide Gel; D004706:Endodeoxyribonucleases; D004720:Endonucleases / Q000302:isolation & purification / Q000378:metabolism; D004722:Endoribonucleases; D005092:Exonucleases / Q000378:metabolism; D001467:Hordeum / Q000201:enzymology; D005779:Immunodiffusion; D008970:Molecular Weight; D009696:Nucleic Acids / Q000494:pharmacology; D010944:Plants / Q000201:enzymology*; D012260:Ribonucleases / Q000037:antagonists & inhibitors / Q000302:isolation & purification*; D013379:Substrate Specificity
chemical_list: D009696:Nucleic Acids; D004706:Endodeoxyribonucleases; D004720:Endonucleases; D004722:Endoribonucleases; D005092:Exonucleases; D012260:Ribonucleases; C022543:ribonuclease T(2); C021835:Serratia marcescens nuclease