Objectives: Staphylococcus epidermidis is the primary causative agent of infections associated with indwelling biomaterials. Antibiotic susceptibility patterns, Biofilm formation capability, and screening of responsible genes in biofilm formation procedure in clinical isolates (icaA, icaB, icaC, icaD, sdrG, and atlE) were assigned as the main objectives in this study. The clinical samples were analyzed via standard biochemical assays for identifying different bacteria which were confirmed using the multiplex colony PCR method. Subsequently, biofilm-formation capability, antibiotic susceptibility testing, and the frequency of genes responsible for biofilm formation in the confirmed strains were checked. Results: Out of 183 clinical specimens 54 S. epidermidis isolates were detected by targeting a housekeeping gene (sesc) taking advantage of the PCR procedure. All of the strains were Biofilm forming producers. The in vitro biofilm formation assays determined that 45 (83.33%), 5 (9.26%), 4 (7.41%) were strong, moderate, and weak biofilm former strains respectively. Among the isolated strains, the specific frequencies of the biofilm-forming genes were specified to be (98%) for sdrG, (84%) for atlE, (80%) for icaC, and (70%) for icaD. Cefamandole and Amikacin are the most effective antibiotics in isolated strains. All strains were ascertained to be methicillin and amoxicillin/clavulanic acid resistant.

Background: Staphylococcus aureus as a causative agent of hospital-acquired infections, has been considered as the primary concern in biomaterial-related infections (BAIs). Following the purification of polysaccharide intercellular adhesion (PIA) as an efficient macromolecule in biofilm formation in the native condition, recombinant S . epidermidis surface exposed rSesC protein, with the most homology to clumping factor A (ClfA) in S. aureus was cloned and expressed in a prokaryotic host as well.Fourier transform infrared spectrometry (FTIR) and Western blotting procedure analyzed purified PIA and protein, respectively. Then, the immune response was evaluated by measuring total IgG titers.Moreover, the capacity of Anti-biofilm forming activity of arisen antibodies to a biofilm forming S. aureus strains was assessed by semi-quantitative micro-plate procedure.Results: Data showed that the total IgGs was boosted in mice immunized sera. By performing inhibition assay, biofilm inhibitory effect of secreted antibodies to test strain was observed. Arisen antibodies against the mixture significantly were more potent than PIA and rSesC, when comparing them in a biofilm inhibition assay. Conclusion: Immunization of mice with mentioned antigens especially a mixture of them, could eliminate the biofilm formation process in S. aureus . Hopefully, this study corresponds the suggestion that, the immunization of mice with PIA and rSesC candidate vaccine could protect against S. aureus infection. Background Staphylococci are opportunistic pathogens and determined as the most common causes of infections related to implanted medical devices, infect both hospitalized patients and immunocompromised individuals [1].Considering diverse virulence factors, such as capsule and cell wall-bound adhesion molecules, surface proteins, toxins, antibiotic resistance, and biofilm formation cause infections in human and animal. [2]. S. aureus is an etiological agent of the mild to severe infections in hospitalized patients, such as bacteremia due to endocarditis, pneumonia, and metastatic infections.Finding revealed that, majority of adults are either permanently or transiently susceptible to colonization by S. aureus. [[3] Up to 20-30% of humans, asymptomatically are colonized by S. aureus

Introduction: Biofilm forming Staphylococcus epidermidis is a main causative agent of infections related to medical devices. Purification and evaluation of Gly-TA polysaccharide from a biofilm-forming S. epidermidis as a putative vaccine candidate were the main goals of the current study. Methods: Taking advantage of size exclusion chromatography procedure, glycerol teichoic acid (Gly-TA) was purified from the above-mentioned strain and biochemical analyses including, Fourier Transform Infrared spectroscopy (FTIR) and Proton Nuclear Magnetic Resonance spectroscopy (H1-NMR) were conducted for the recovered polysaccharide. Results: Following PCR confirmation of a S. epidermidis strain, Gly-TA was extracted and its biochemical compositions (i.e. N-acetyl glucose amine residues) were obtained. Conclusion: It is envisaged that Gly-TA polysaccharide could be considered as a putative vaccine to inhibit formation of biofilm by S. epidermidis.