title: Combinatorial biochemistry and shuffling of TEM, SHV and Streptomyces albus omega loops in PSE-4 class A beta-lactamase.
abstract: The class A PSE-4 beta-lactamase was used for studying the importance of amino acids in the omega (Omega) loop and its interactions for hydrolysis of beta-lactam antibiotics. By cassette mutagenesis, we replaced the amino acids 163-179 Omega loop in PSE-4 with TEM-1, SHV-1 and Streptomyces albus G beta-lactamase Omega loops. Phenotypic analysis of Escherichia coli recombinants expressing the Omega loop PSE-4 mutant enzymes gave MICs and kinetic data similar to those of wild-type PSE-4.
authors.affiliation: Microbiologie Moléculaire & Génie des Protéines, Sciences de la Vie et de la Santé, Faculté de Médecine, Pavillon Charles-Eugène Marchand, Université Laval, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Sanschagrin
authors.forename: E
authors.initials: E
authors.lastname: Thériault
authors.forename: Y
authors.initials: Y
authors.lastname: Sabbagh
authors.forename: N
authors.initials: N
authors.lastname: Voyer
authors.forename: R C
authors.initials: RC
authors.lastname: Levesque
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D007700:Kinetics; D016254:Mutagenesis, Insertional / Q000235:genetics; D010641:Phenotype; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism*
chemical_list: C054882:beta-lactamase PIT-2; C410213:beta-lactamase PSE-4; D001618:beta-Lactamases; C034413:beta-lactamase TEM-1