Cheng, Y. S., Zipser, D. (June 1979) Purification and characterization of protease III from Escherichia coli. J Biol Chem, 254 (11). pp. 4698-706. ISSN 0021-9258 (Print)0021-9258 (Linking)
Abstract
An endoproteolytic enzyme of Escherichia coli, designated protease III, has been purified about 9,600-fold to homogeneity with a 6% yield. The purified enzyme consists of a single polypeptide chain of Mr 110,000 and is most active at pH 7.4. Protease III is very sensitive to metal-chelating agents and reducing agents. The EDTA-inactivated enzyme can be reactivated by Zn2+, Co2+ or Mn2+. Protease III is devoid of activity toward aminopeptidase, carboxypeptidase, or esterase substrates but rapidly degrades small proteins. When fragments of beta-galactosidase are used as substrates for protease III, the enzyme preferentially degrades proteins with molecular weights of less than 7,000. Protease III cleaves the oxidized insulin B chain at two sites with an initial rapid cleavage at Tyr-Leu (16-17) and a second slower cut at Phe-Tyr (25-26).
| Item Type: | Paper |
|---|---|
| Uncontrolled Keywords: | Cations, Divalent Drug Stability Endopeptidases/isolation & purification/*metabolism Escherichia coli/*enzymology Kinetics Molecular Weight Substrate Specificity |
| Subjects: | organism description > bacteria > escherichia coli bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > enzymes > Protease |
| CSHL Authors: | |
| Communities: | CSHL labs |
| Depositing User: | Matt Covey |
| Date: | 10 June 1979 |
| Date Deposited: | 26 May 2016 16:35 |
| Last Modified: | 26 May 2016 16:35 |
| Related URLs: | |
| URI: | https://repository.cshl.edu/id/eprint/32669 |
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