Correlation bewteen associated genes and biofilm phenotype in Staphylococcus epidermidis / 国际检验医学杂志

ABSTRACT

Objective To investigate the relationship of icaA,aap ,atlE,sarA gene with biofilm phenotype in Staphyloccus epi-dermidis .Methods Tissue culture plates assays were used to assess biofilm-forming ability of 78 Staphyloccus epidermidis strains.The presence of icaA,atlE,aap ,sarA gene was amplified with PCR method,the relationship between these genes and bio-film phenotype was evaluated by χ2 test and the difference of the biofilm OD′s value in TSB and TSB+3% NaCl by icaA + strains and icaA - strains was evaluated by Wilcoxon sign test,respectively.Results The positive rates of icaA,atlE,aap ,sarA gene were 24.4%(19/78),79.5%(62/78),73.8%(57/78),82.1%(64/78),respectively.40 biofilm-positive strains were detected(51.3%), among which 16 strains carried icaA gene,24 strains showed weak biofilm-forming ability.Those genes above with biofilm forma-tion were statistically correlated.Moreover,there was a relation between the icaA gene and the high biofilm-producing phenotype. There was a significant difference between the biofilm OD values in TSB and TSB+3% NaCl by icaA + strains and icaA - strains, respectively.Conclusion Multiple genes are involved in Staphylococcus epidermidis biofilm-positive phenotype,but the icaA gene contributes to the high biofilm-forming phenotype.Biofilm phenotype is also influenced by environmental factors.