Abstract
A protein inhibitor of cysteine proteinases, "stefin", was purified from cytosol of human polymorphonuclear granulocytes. Affinity chromatography on carboxymethylated papain-Sepharose was used as the first step, followed by ion exchange chromatography on DEAE-Sephacel, which resolved four inhibitory peaks. The main peak, comprising approx. 80% of total inhibitory activity was characterized. It was found to be a homogenous protein with an apparent molecular mass slightly lower than that of cytochrome c and with an isoelectric point of 4.65. The inhibitor inhibits papain at a molar ratio of 1:1 as well as cathepsin B and H, but it does not inhibit serine and aspartic proteinases. It is stable at elevated temperature and in alkaline pH, but looses its activity in acid pH. Oxidized glutathione has no effect on its inhibitory activity.
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 callMore From: Hoppe-Seyler´s Zeitschrift für physiologische Chemie
Disclaimer: 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.
