title: A simple method of markerless gene deletion in Staphylococcus aureus.
abstract: Staphylococcus aureus is a Gram-positive pathogen that causes opportunistic infections and a wide variety of diseases. Methicillin-resistant S. aureus (MRSA) is frequently isolated as multidrug-resistant in nosocomial and community infections. Molecular genetic manipulation is an important tool for understanding the molecular mechanism of S. aureus infection. However the number of available antibiotic markers is limited due to multidrug resistance. In this study, we constructed two Escherichia coli-S. aureus shuttle vectors, pKFT and pKFC, that carry a temperature-sensitive origin of replication in S. aureus, lacZ(a) enabling a simple blue-white screening in E. coli, an ampicillin resistant gene, and either a tetracycline resistance gene or a chloramphenicol resistance gene. We report a simple technique using pKFT to construct a markerless gene deletion mutant in S. aureus by allelic replacement without the use of a counter-selection marker. Subculture twice at 25°C was critical to promote an allelic exchange rate in S. aureus. This technique is very simple and useful to facilitate genetic research on S. aureus.
authors.affiliation: Department of Bacteriology, Hiroshima Univeristy Graduate School of Biomedical Sciences, Hiroshima 734-8851, Japan.
authors.forename: Fuminori
authors.initials: F
authors.lastname: Kato
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Sugai
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics; D017353:Gene Deletion; D055786:Gene Knockout Techniques / Q000379:methods*; D005818:Genetic Engineering; D059765:Homologous Recombination; D010957:Plasmids / Q000235:genetics; D013211:Staphylococcus aureus / Q000235:genetics* / Q000254:growth & development
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C476149:SarS protein, Staphylococcus aureus