Venema G, Pritchard RH, Venema-Schroeder T: Fate of transforming deoxyribonucleic acid in Bacillus subtilis. J Bacteriol 1965, 89:1250–1255.PubMed 38. Kuipers OP, Rollema HS, Yap WM, Boot HJ, Siezen RJ, de Vos WM: Engineering dehydrated amino acid residues in the antimicrobial peptide nisin. J Biol
Chem 1992, 267:24340–24346.PubMed Authors’ contributions MJGB and ATK contributed equally to this work. MJGB carried out the microarray experiments and wrote the manuscript, ATK performed the quantitative RT-PCRs and overexpression of BC4207 and was involved in writing the manuscript, AMM participated in the design of the growth assay and microarray experiments, AH helped to obtain the purified AS-48 bacteriocin, AG and OPK conceived and coordinated the project, and corrected Selleckchem mTOR inhibitor the manuscript. All authors have read and approved the manuscript.”
One of the defense mechanisms Tanespimycin in vivo of Staphylococcus aureus is the capacity to form biofilms. Bacteria embedded in biofilms are often difficult to eradicate with standard antibiotic regimens and inherently resistant to host immune responses [1, 2]. As a result, treatment of many chronic S. aureus biofilm related infections, including endocarditis, osteomyelitis and indwelling medical device infections is hindered . Biofilm STI571 molecular weight formation is a multistep process, starting with transient adherence to a surface. Subsequently, specific bacterial adhesins, referred to as microbial surface components recognizing adhesive matrix
molecules (MSCRAMMS) promote the actual attachment . Next, during the accumulation phase, bacteria stick to each other and production of extracellular polymeric substances (EPS) and/or incorporation of host derived components, such as platelets, takes place, resulting OSBPL9 in a mature biofilm. In circumstances of nutrient deprivation, or under heavy shear forces, detachment of bacteria appears through autonomous formation of autoinducing peptides (AIP) , with release and dispersal of bacteria as a consequence. It has been shown that expression of the accessory gene regulator (agr) locus, encoding a quorum-sensing system, results in expression of surfactant-like molecules, such as δ-toxin , contributing to the detachment. Essential for biofilm development in S. aureus is the regulatory genetic locus staphylococcal accessory regulator (sarA), which controls the intracellular adhesin (ica) operon and agr regulated pathways . It has been suggested that biofilm formation in methicillin-resistant S. aureus (MRSA) is predominantly regulated by surface adhesins, which are repressed under agr expression, while biofilm formation in methicillin-susceptible S. aureus (MSSA) is more dependent on cell to cell adhesion by the production of icaADBC-encoded polysaccharide intercellular adhesin (PIA), also referred as poly-N-acetylglucosamine (PNAG) or slime . However a clear role for the ica locus of S. aureus is not as evident as that of Staphylococcus epidermidis .