title: Complete amino acid sequence of p453-plasmid-mediated PIT-2 beta-lactamase (SHV-1).
abstract: The complete amino acid sequence of the p453-plasmid-mediated PIT-2 beta-lactamase (SHV-1) was determined. The protein contains 265 residues. Peptides resulting from digestions with trypsin, Staphylococcus aureus V8 proteinase, chymotrypsin and Lys-C proteinase and cleavage with CNBr were separated and purified by using reverse-phase h.p.l.c. The amino acid sequence of each peptide was manually determined with the dimethylaminoazobenzene isothiocyanate/phenyl isothiocyanate double-coupling method. The primary structure of PIT-2 beta-lactamase was compared with those of two closely related enzymes, namely TEM-1 beta-lactamase and the beta-lactamase of Klebsiella pneumoniae strain LEN-1. The PIT-2 beta-lactamase amino acid sequence was strongly retained, with respectively 68% and 88% homology. Thus PIT-2 enzyme could represent an evolutionary step between a chromosomally encoded beta-lactamase and the plasmid-mediated TEM beta-lactamases.
authors.affiliation: Muséum National d'Histoire Naturelle, C.N.R.S. U.A. 401, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Barthélémy
authors.forename: J
authors.initials: J
authors.lastname: Peduzzi
authors.forename: R
authors.initials: R
authors.lastname: Labia
mesh_terms: D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000302:isolation & purification; D010957:Plasmids; D001618:beta-Lactamases
chemical_list: D010446:Peptide Fragments; C054882:beta-lactamase PIT-2; D001618:beta-Lactamases