title: Purification and characterization of extracellular proteinases of Aspergillus oryzae.
abstract: The extracellular proteinases of Aspergillus oryzae EI 212 were separated into two active fractions by (NH4)2SO4 and ethanol fractionation followed by diethylaminoethyl-Sephadex A-50 and hydroxyapatite chromatography. The molecular weight was estimated by gel filtration to be about 70,000 and 35,000 for proteinases I and II, respectively. Optimum pH for casein and hemoglobin hydrolysis was 6.5 at 60 C for proteinase I and 10.0 at 45 C for proteinase II, and for gelatin hydrolysis it was 6.5 at 45 C for both enzymes. The enzymes were stable over the pH range 6 to 8 at 30 C for 60 min. The enzyme activity for both the proteinases was accelerated by Cu2+ and inhibited by Fe2+, Fe3+, Hg2+, and Ag+. Halogenators (e.g., N-chlorosuccinimide) and diisopropyl fluorophosphate inhibited proteinase II. Sulfhydryl reagents such as p-chloromercuribenzoate and iodoacetate inhibited proteinase I. Sulfhydryl compounds accelerated the action of both enzymes.
mesh_terms: D000645:Ammonium Sulfate; D001230:Aspergillus / Q000201:enzymology*; D001236:Aspergillus oryzae / Q000201:enzymology*; D002364:Caseins / Q000378:metabolism; D002474:Cell-Free System; D011232:Chemical Precipitation; D002845:Chromatography; D000431:Ethanol; D006454:Hemoglobins / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism; D008670:Metals / Q000494:pharmacology; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000302:isolation & purification / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000494:pharmacology; D013439:Sulfhydryl Reagents / Q000494:pharmacology; D014508:Urea / Q000494:pharmacology
chemical_list: D002364:Caseins; D006454:Hemoglobins; D007527:Isoenzymes; D008670:Metals; D013438:Sulfhydryl Compounds; D013439:Sulfhydryl Reagents; D000431:Ethanol; D014508:Urea; D010447:Peptide Hydrolases; D000645:Ammonium Sulfate