Abstract
A newly recognized peptidase, designated proteinase yscD, was purified from the yeast Saccharomyces cerevisiae. The enzyme cleaves the Pro-Phe bond of the synthetic peptide substrate Bz-Pro-Phe-Arg-4-nitroanilide and the Ala-Ala bond of Ac-Ala-Ala-Pro-Ala-4-nitroanilide, Ac-Ala-Ala-Pro-Phe-4-nitroanilide, and MeO-Suc-Ala-Ala-Pro-Met-4-nitroanilide with high efficiency (Bz-, Ac-, and MeO-Suc are defined as benzoyl, acetyl, and methoxy-succinyl, respectively). [3H]Methylcasein does not serve as a substrate. Optimum pH for cleavage of Bz-Pro-Phe-Arg-4-nitroanilide is in the range of 6.5 to 7; for Ac-Ala-Ala-Pro-Ala-4-nitroanilide the range is between 5.75 and 6. For MeO-Suc-Ala-Ala-Pro-Met-4-nitroanilide the pH optimum was found to be 5.5. The purified enzyme has an apparent Stokes radius of Rs = 37.9 A as judged by gel chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicates a molecular weight of approximately 83,000 for the enzyme. Mercurials and EDTA were found to be potent inhibitors of proteinase yscD activity.
Highlights
A newly recognized peptidase, designated proteinase Using chromogenic peptide substrateswe recently detected yscD, waspurified from the yeast Saccharomyces cere- a completely newproteolytic systemin yeast
Optimum pH for cleavage of Bz-Pro-Phe-Arg-4-nitroanilide is in the range of 6.5 to 7; for Ac-Ala-Alaactivities detectable with chromogenic substrates [6] we describe here the purification and characterization of another new enzyme active against chromogenic substrates which we call proteinase yscD
Analysis of the reaction products by thin-layer chromatography or analysis with HPLCand subsequent amino acid analysis of the hydrolyzed peptide products revealed that cleavage of Bz-Pro-Phe-Arg-NA occurred at the Pro-Phe (AA-3-AA-2) bond whereas the chromogenic substrates Ac-Ala-Ala-Pro-Ala-NA,MeO-Suc-Ala-Ala-Pro-Metpurification steps based on the availability of protein SH groups and which separates according to size
Summary
A newly recognized peptidase, designated proteinase Using chromogenic peptide substrateswe recently detected yscD, waspurified from the yeast Saccharomyces cere- a completely new (end0)proteolytic systemin yeast Optimum pH for cleavage of Bz-Pro-Phe-Arg-4-nitroanilide is in the range of 6.5 to 7; for Ac-Ala-Alaactivities detectable with chromogenic substrates [6] we describe here the purification and characterization of another new enzyme active against chromogenic substrates which we call proteinase yscD.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
