Analysis of the polymorphism of Staphylococcus strains isolated from a hospital environment

Abstract

Nosocomial infections, despite the introduction of the numerous control systems, still constitute a considerable problem in hospitals. They are of great socio-economic importance due to the prolonged stay of patients in hospitals and high treatment costs. They also contribute to an increase in the death rate. For many years staphylococci have remained at the top of the list of microorganisms that cause infections in hospitals. The methicillin-resistant staphylococci (MRSA) strains that occur among both coagulase positive and coagulase negative (MRCNS) species are particularly dangerous. The aim of the presented paper was to determine the usefulness of the 16S rRNA gene sequence analysis and the region between the genes coding 16 S and 23 S rRNA for an examination of the diversity of Staphylococcus spp. isolated from a hospital environment and to perform a polymorphism analysis within and among the species. We also analyzed the polymorphism of 84 Staphylococcus strains and isolated from a hospital environment using PCR-RFLP and ITS PCR methods. A restriction enzyme analysis of the 16 S rRNA gene using TaqI enzyme did not show any considerable power of differentiation in relation to the Staphylococci strains examined. However, the variable region between genes 16 S and 23S rRNA showed a high degree of polymorphisms and allowed for the differentiation of the hospital strains examined. The results demonstrated the highest differentiation inStaphylococcus aureus strains. The examined strains originating from hospital environment are characterised by a high polymorphism. Key words: ITS-PCR, Staphylococcus spp., hospital infections, 16 S rRNA, 23 S rRNA.