Purification and characterization of a new ribonuclease from fruiting bodies of the oyster mushroom Pleurotus ostreatus

✍ Scribed by X. Y. Ye; Dr T. B. Ng

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 93 KB
• Volume: 9
• Category: Article
• ISSN: 1075-2617
• DOI: 10.1002/psc.437

✦ Synopsis

Abstract

A ribonuclease (RNase), possessing an N‐terminal sequence disparate from those of ribonucleases from other mushrooms and previously isolated Pleurotus ostreatus RNases, was purified from the fruiting bodies of the edible mushroom Pleurotus ostreatus. The N‐terminal sequence of Pleurotus ostreatus RNase did not manifest homology even to a previously reported RNase from the same mushroom. The ribonuclease was adsorbed on CM‐Sepharose and Mono S. It exhibited a molecular mass of 12 kDa in both sodium dodecyl sulphate‐polyacrylamide gel electrophoresis and gel filtration on Superdex 75. The ribonuclease displayed an activity of 11 490 U/mg on yeast tRNA. The highest ribonuclease activity was exhibited toward poly U, followed by poly A and poly C. No activity was shown toward poly G. The optimal pH for its activity was 7 and the optimal temperature was 55°C. It inhibited cell‐free translation in a rabbit reticulocyte lysate with an IC~50~ of 240 nM. Copyright © 2003 European Peptide Society and John Wiley & Sons, Ltd.