Structure of peptide from active site region of Escherichia coli L-asparaginase.
Article Details
- CitationCopy to clipboard
Peterson RG, Richards FF, Handschumacher RE
Structure of peptide from active site region of Escherichia coli L-asparaginase.
J Biol Chem. 1977 Mar 25;252(6):2072-6.
- PubMed ID
- 321449 [ View in PubMed]
- Abstract
The L-asparagine analogue 5-diazo-4-oxo-L-[5-14C]norvaline binds irreversibly to the active site of Escherichia coli L-asparaginase. Conditions for optimal labeling in buffers containing 50% dimethylsulfoxide have been developed and kinetic parameters of the inactivation have been determined. After reduction, alkylation and subsequent degradation of the modified enzyme with alpha-chymotrypsin, the principal radioactive decapeptide of sequence Val-Gly-Ala-Met-Arg-Pro-Ser-Thr-Ser-Met was isolated. A second radioactive hexapeptide Arg-Pro-Ser-Thr-Ser-Met resulting from chymotryptic digestion of the decapeptide was also isolated. Evidence is presented for the attachment of the 5-diazo-4-oxo-L-norvaline residue to serine-9 in the decapeptide via an acid-labile linkage.