title: Isolation and characterization of carboxylesterase E3 from Salmonella enterica.
abstract: Three esterases (Est-) hydrolysing alpha-naphthyl acetate: Est-E1, Est-E3 and Est-E4 produced by Salmonella enterica serovar Typhimurium, strain LT2 were separated by DEAE chromatography and gel filtration. Est-E3, the major component of this set of enzymes, clearly differed from the two other esterases by its apparent molecular weight, titration curve, substrate specificity and inactivation. Immunoglobulins raised against Est-E3 completely neutralized the activity of Est-E3 but did not react with Est-E1 or Est-E4; it showed no cross reaction with carboxylesterase B of Escherichia coli or with carboxylesterases from other enterobacteria. Est-E3 showed electrophoretic variants which were biochemically and immunologically detected in the seven subspecies of the genus Salmonella. These findings suggest that variants of Est-E3 are the products of very closely related loci originating from a common ancestral gene. The esterase could be a phylogenetic marker of the genus and a suitable molecular tool for taxonomy and epidemiology.
authors.affiliation: Laboratoire de Microbiologie, Faculté de Médecine X. Bichat, Université Paris 7, France.
authors.forename: A
authors.initials: A
authors.lastname: Brisabois
authors.forename: P
authors.initials: P
authors.lastname: Goullet
mesh_terms: D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D007136:Immunoglobulins; D007527:Isoenzymes / Q000302:isolation & purification* / Q000378:metabolism; D007700:Kinetics; D008970:Molecular Weight; D009500:Neutralization Tests; D012475:Salmonella / Q000201:enzymology*; D013696:Temperature
chemical_list: D007136:Immunoglobulins; D007527:Isoenzymes; D002265:Carboxylic Ester Hydrolases