title: Extracellular RNase produced by Yarrowia lipolytica.
abstract: Production of extracellular RNase(s) by Yarrowia lipolytica CX161-1B was examined in media between pHs 5 and 7. RNase production occurred during the exponential growth phase. High-molecular-weight nitrogen compounds supported the highest levels of RNase production. Several RNases were detected in the supernatant medium. Based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the RNases had estimated molecular weights of 45,000, 43,000, and 34,000. It was found that Y. lipolytica secretes only one RNase (the 45,000-molecular-weight RNase) and that the 43,000 and 34,000-molecular-weight RNases are degradation products of this RNase. The alkaline extracellular protease secreted by Y. lipolytica was shown to have a major role in the 45,000- to 43,000-molecular-weight conversion, and it was demonstrated that the 45,000-molecular-weight RNase could be purified from a mutant which does not produce the alkaline extracellular protease. Purification of the RNase from a wild-type strain resulted in purification of the 43,000-molecular-weight RNase. This RNase was a glycoprotein with a molecular weight of 44,000 as estimated by gel filtration, an isoelectric point of pH 4.8, and a pH optimum between 6.5 and 7.0.
mesh_terms: D003470:Culture Media; D007124:Immunoenzyme Techniques; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000378:metabolism; D012260:Ribonucleases / Q000032:analysis / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism; D004718:Saccharomycetales / Q000201:enzymology* / Q000254:growth & development
chemical_list: D003470:Culture Media; D012260:Ribonucleases; D010447:Peptide Hydrolases