title: Effect of incubation atmosphere on the production and composition of staphylococcal biofilms.
abstract: Staphylococcus aureus and Staphylococcus epidermidis are pathogenic bacteria that often cause invasive infections in humans. In this study, we characterized the composition and growth characteristics of staphylococcal biofilms under various incubation atmospheres. We assessed the effect of incubation atmosphere (aerobic, 5% CO2, anaerobic, and microaerobic) on the biofilm production capabilities of S. aureus strains isolated from healthy volunteers and from patients with catheter-related bloodstream infection. In addition, the composition of S. aureus and S. epidermidis biofilms was determined by assessment of biofilm degradation after treatment with DNase I, proteinase K, and dispersin B. The strains obtained from healthy volunteers and patients showed similar biofilm formation capabilities. Biofilms of S. aureus were rich in proteins when developed under ambient atmospheric conditions, 5% CO2, and microaerobic condition, whereas S. epidermidis biofilms contained large amounts of poly-β (1, 6)-N-acetyl-D-glucosamine when developed under ambient atmospheric conditions and microaerobic condition. The biofilm-producing capability of S. epidermidis was considerably higher than that of S. aureus under aerobic condition. Staphylococcal isolates obtained from healthy individuals and patients with catheter-related infections have similar biofilm-forming capabilities. Under microaerobic conditions, S. aureus and S. epidermidis form protein-rich and poly-β (1, 6)-N-acetyl-D-glucosamine-rich biofilms, respectively. These components may play an important role in the development of biofilms inside the body and may be the target molecules to prevent catheter-related infections caused by these organisms.
authors.affiliation: Department of Bacteriology, Nagoya University Graduate School of Medicine, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Asai
authors.affiliation: Department of Bacteriology, Nagoya University Graduate School of Medicine, Japan. Electronic address: yakeiko@med.nagoya-u.ac.jp.
authors.forename: Keiko
authors.initials: K
authors.lastname: Yamada
authors.affiliation: Department of Infectious Diseases, Centre of National University Hospital for Infection Control, Nagoya University Hospital, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yagi
authors.affiliation: Department of Infectious Diseases, Kanazawa Medical University, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Baba
authors.affiliation: Division of Infectious Diseases, Shizuoka Cancer Center, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawamura
authors.affiliation: Department of Nursing, School of Nursing, Sugiyama Jogakuen University, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Ohta
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D018441:Biofilms / Q000254:growth & development*; D002245:Carbon Dioxide / Q000378:metabolism; D055499:Catheter-Related Infections / Q000382:microbiology; D006801:Humans; D016133:Polymerase Chain Reaction; D013203:Staphylococcal Infections / Q000382:microbiology; D013211:Staphylococcus aureus / Q000502:physiology*; D013212:Staphylococcus epidermidis / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D002245:Carbon Dioxide
keywords: Biofilm composition; Extracellular DNA; Microbial surface components recognizing adhesive matrix molecules; Poly-β (1,6)-N-acetyl-(D)-glucosamine; Staphylococcus aureus; Staphylococcus epidermidis