title: Purification and properties of two neutral proteinases from Aspergillus nidulans.
abstract: Two proteinases have been purified from mycelial extracts of Aspergillus nidulans. Both enzymes have pH optima between 6.5 and 7.5 and are inhibited by phenylmethane sulphonyl fluoride and by di-isopropyl fluorophosphate. The molecular weights and isoelectric points of proteinase I and proteinase II are 30 900 and 30 000, and 4.6 and 4.3, respectively. Both enzymes have a similar range of substrate specificities. The principal differences in their properties are that proteinase I is sensitive to inhibition by 1 mM mercurials whereas proteinase II is not appreciably inhibited at this concentration, and that proteinase I is much more sensitive to denaturation by urea, guanidine hydrochloride and sodium dodecyl sulphate.
mesh_terms: D001233:Aspergillus nidulans / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D010450:Endopeptidases / Q000302:isolation & purification* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D008970:Molecular Weight; D011480:Protease Inhibitors / Q000494:pharmacology; D011489:Protein Denaturation; D013379:Substrate Specificity; D014508:Urea / Q000494:pharmacology
chemical_list: D011480:Protease Inhibitors; D014508:Urea; D010450:Endopeptidases