Susceptibility patterns and the role of extracellular DNA in Staphylococcus epidermidis biofilm resistance to physico-chemical stress exposure

• DOI: 10.1186/s12866-018-1183-y
• Publication Date: 2018-05-02T03:51:39Z
• Authors: Charles Ochieng’ ...; Paul Oyieng’ Ang’...; David Miruka Onyango; Daniel Otieno Ochiel
• Keywords: Parasitology

Over 65% of human infections are ascribed to bacterial biofilms that often highly resistant antibiotics and host immunity. Staphylococcus epidermidis is the predominant cause recurrent nosocomial biofilm-related infections. However, susceptibility patterns S. physico-chemical stress induced by commonly recommended disinfectants [(heat, sodium chloride (NaCl), hypochlorite (NaOCl) hydrogen peroxide (H2O2)] in domestic healthcare settings remains largely unknown. Further, molecular mechanisms resistance stresses remain unclear. Growing evidence demonstrates extracellular DNA (eDNA) protects against antibiotics. role eDNA as a potential mechanism underlying exposure yet be understood. Therefore, this study aimed evaluate release biofilm planktonic cells exposure. exposed conditions for disinfection [heat (60 °C), 1.72 M NaCl, solution containing 150 μL waterguard (0.178 NaOCl) 1 L water or 1.77 H2O2] 30 60 min exhibited lower log reductions CFU/mL than corresponding (p < 0.0001). The released sub-lethal heat (50 °C)-treated was not statistically different = 0.8501). 50 °C-treated significantly increased untreated controls 0.0098). 0.8 NaCl-treated 0.9697). Conversely, 5 mM NaOCl-treated 0.0015). μM H2O2-treated more 0.021). were less susceptible four analogous cells. enhanced response oxidative suggesting stresses.