title: Biofilm formation by Staphylococcus hominis strains isolated from human clinical specimens.
abstract: Staphylococcus hominis is the third species of coagulase-negative staphylococci (CoNS) most frequently isolated from specimens of patients with hospital-acquired infections. Many infections caused by CoNS appeared to be associated with biofilms. Nevertheless, the knowledge of the ability of S. hominis to form a biofilm is limited. The aim of this study was to analyze the formation of the biofilm by 56 S. hominis strains isolated from clinical cases. The biofilm three-dimensional structure was reconstructed by confocal laser scanning microscopy. We found that most of S. hominis strains carried icaADBC genes encoding polysaccharide intercellular adhesin (PIA), which plays a crucial role in the formation of biofilms in staphylococci strains. However, only a half of the ica-positive strains had an ability to form a biofilm in vitro. In this study, we also accessed the sensitivity of biofilms of S. hominis strains to sodium metaperiodate, proteinase K and DNase. We found that polysaccharides and proteins are the major components of the extracellular matrix of the biofilm formed by S. hominis. DNase did not have a significant effect on biofilms, which suggested that nucleic acid plays a minor role in the mature biofilm.
authors.affiliation: Department of Microbiology, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Umultowska 89, 61-614, Poznań, Poland, ewasz@amu.edu.pl.
authors.forename: Ewa
authors.initials: E
authors.lastname: Szczuka
authors.forename: Kinga
authors.initials: K
authors.lastname: Telega
authors.forename: Adam
authors.initials: A
authors.lastname: Kaznowski
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018441:Biofilms; D006801:Humans; D013203:Staphylococcal Infections / Q000382:microbiology*; D041181:Staphylococcus hominis / Q000235:genetics / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins