Better understanding the process and mechanisms of Se biofilm self-renewal in patients will help us develop more effective strategies against Se biofilm-related infection. Acknowledgement This work was supported by grants from the National Natural Science IWR 1 Foundation for Young Scientist of China (81101791 to Z.Q.). Z.Q. was also supported by the DANIDA fellowship during his visit at DTU. L.Y. was supported by a grant from the Danish Research Council

for Independent Research (09-073917). Electronic supplementary material Additional file 1: Figure S1. S. epidermidis 1457 agr mutation does not affect bacterial growth. Growth curves for S. epidermidis 1457 wild type and agr mutant and agr/atlE double mutant cultivated in TSB batch cultures are shown. GSK621 Data shown represent one of 3 independent experiments. (TIFF 62 KB) Additional file 2: Figure S2. S. epidermidis isolates associated with catheter infection exhibit differential expression of genes associated with biofilm formation. The expression profiles Temsirolimus of RNAIII, atlE and icaA were compared for 6-d biofilm cells of laboratory strain and clinical isolates using qRT-PCR as described in Methods. Error bars represent the S.E.M.

for three independent experiments. (TIFF 97 KB) Additional file 3: Figure S3. S. epidermidis agr system regulates cell autolysis through atlE. Triton X-100 induced cell autolysis assays were performed as described in Methods, and error bars represent the S.E.M. for three independent experiments. (TIFF 77 KB) Additional file 4: Figure S4. Sequence alignment analysis of agr conserved regions from ATCC 35984, Se-1, Se-2 and Se-3. The agr conserved regions Cytidine deaminase were amplified

and sequenced as described in Methods, then alignment analysis was performed by using Vector NTI Advance 9 software (Invitrogen). (PDF 69 KB) Additional file 5: Table S1. Primer sequences for qRT-PCR in this study. (DOCX 16 KB) References 1. Raad II, Bodey GP: Infectious complications of indwelling vascular catheters. Clin Infect Dis 1992,15(2):197–208.PubMedCrossRef 2. Rupp ME, Archer GL: Coagulase-negative staphylococci: pathogens associated with medical progress. Clin Infect Dis 1994,19(2):231–243. quiz 244–235PubMedCrossRef 3. von Eiff C, Peters G, Heilmann C: Pathogenesis of infections due to coagulase-negative staphylococci. Lancet Infect Dis 2002,2(11):677–685.PubMedCrossRef 4. Vadyvaloo V, Otto M: Molecular genetics of Staphylococcus epidermidis biofilms on indwelling medical devices. Int J Artif Organs 2005,28(11):1069–1078.PubMed 5. Gotz F: Staphylococcus and biofilms. Mol Microbiol 2002,43(6):1367–1378.PubMedCrossRef 6.