title: Genetic heterogeneity in methicillin-resistant strains of Staphylococcus aureus revealed by esterase electrophoretic polymorphism.
abstract: 136 methicillin-resistant strains of Staphylococcus aureus recovered from hospitalized patients in 18 countries were characterized by electrophoretic mobilities of three types of esterases. These were defined by their ranges of activity toward five synthetic substrates and their resistance to di-isopropyl fluorophosphate. Fourteen zymotypes were distinguished. Two, designated as 6 and 14, were found in 53 and 50 strains, respectively. Genetic diversity coefficients were lower for strains from France and from other European countries (H = 0.47 and 0.53, respectively) than for strains from North America (H = 0.79). On the basis of electrophoretic polymorphism of esterases, our work provides evidence that methicillin-resistance is expressed in genetically different strains. Variations in esterase electrophoretic pattern within methicillin-resistant strains of S. aureus can make a significant contribution to the study of their epidemiology.
authors.affiliation: Laboratoire de Microbiologie, Faculté de Médecine Xavier-Bichat, Université Paris VII, France.
authors.forename: C
authors.initials: C
authors.lastname: Branger
authors.forename: P
authors.initials: P
authors.lastname: Goullet
mesh_terms: D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D004587:Electrophoresis, Agar Gel; D005602:France; D006801:Humans; D008712:Methicillin / Q000627:therapeutic use; D010403:Penicillin Resistance; D011110:Polymorphism, Genetic; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D008712:Methicillin