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Purified, recombinant forms of selected antigens from the methicillin-resistant Staphylococcus aureus (MRSA) and biofilm-upregulated, cell wall-associated proteins are used to create immunoglobulin G (IgG) antibodies.

The hydrolysis of heat-killed cells of Staphylococci by recombinant [phi]11 and [phi]12 endolysins is studied. The dissolution of biofilm by the endolysins is found to be the key factor in the accumulation of antibiotics in the cell walls.

The immunoglobulin G (IgG) binding ZZ domain of protein A from Staphylococcus aureus is fused to the N terminus of the polyhydroxyalkanoate (PHA) synthase from Cupriavidus necator. The fusion protein is confirmed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry and mediated formation of ZZ domain-displaying PHA granules in recombinant Escherichia coli.

Research has been conducred on aureocin A53. The action mode of this aureocin on bacterial cells and model membranes has been investigated, and the results suggest that aureocin's bacteriocidal activity derives from membrane permeabilization.

Research has been conducted on Staphylococcus aureus cells in biofilms. The disinfectant test developed for these cells and the membrane-active compound benzalkonium chloride and oxidizing agent hypochlorite used in this test are discussed.

Staphylococcus aureus NaCl-sensitive mutants exhibiting Tn917-lacZ insertions were analyzed by Southern blotting to determine the osmoregulatory mechanisms of the pathogenic microbe. The Staphylococcus aureus mutants with Tn917-induced NaCl-sensitivity exhibited high levels of L-[14C]proline and [14C]glycine betaine uptake under hyperosmotic stress. The levels of K+, proline and glycine betaine uptake were also similar between wild-type and mutant strains. However, the production of NaCl stress proteins was impaired by the presence of glycine betaine.

The effects of four liquid repair media (1% powdered skim milk in distilled water (PSM), complex medium, M9 minimal salt medium and saline solution) on the repair and enterotoxin production by four heat-shocked Staphylococcus aureus strains (FRI-100, FRI-137, FRI-472 and S6) were studied. Salt tolerance was used as a measure of the repair of damaged cells. PSM was the most efficient medium for promoting the repair of stressed cells. Enterotoxins were observed in all strains after 10 h.

Quantitative assays for lipase activity are generally complicated procedures requiring the use of specialized instruments. A simple, less expensive procedure for the quantitative determination of lipase activity in culture supernatants of Staphylococcus aureus was developed. The procedure exploits the ability of lipase to induce clearing of tributyrin emulsions. Tributyrin clearance is measured in plate assays by spectorphotometric analysis. Tests showed that the procedure is sensitive to 1.0 micrograms of lipase per milliliter, and under the prescribed conditions, is specific for lipase detection.

Staphylococcus aureus produces enterotoxins within various foods. This enterotoxin-producing ability is favored by several conditions such as low-water activity. Osmotic stimulation of this bacterium makes it fairly adaptable to low-water activity environments. This study shows the presence of two proline transport systems within the whole cells of Staphylococcus aureus to which its osmotolerance is attributed. One of the transport system, the low-affinity transport system, seems to be the primary system responsible for the uptake of proline. This system is triggered by sodium chloride concentrations and exposure to high concentrations of non-permeating solutes, both ionic and non-ionic.The osmoregulatory properties of this microorganism may be explained more by futurestudies following identification of the transport systems in this study.

The three genes in the iron-hydroxamate uptake system in Staphylococcus aureus appear to code for an ATP-binding protein and two ferrichrome permeases. The operon resembles an ATP-binding cassette transporter and it is specific for iron-bound siderophores.

The high hydrostatic pressure (HHP) inactivation kinetics of eight strains of Staphylococcus aureus is studied by analyzing separately the different phases of inactivation, including shoulders, log-linear phases of inactivation and tails. The causes of deviations of the first-order kinetics are explored by emphasizing the appearance of sublethal damage.

The impact of subinhibitory concentrations of eugenol on the expression of the major exotoxins produced by Staphylococcus aureus is examined. The results have shown that eugenol has the potential to be rationally applied on food products as a novel food antimicrobial agent both to inhibit the growth of bacteria and to suppress the production of exotoxins by Staphylococcus aureus.

A study was conducted to directly observe the cell growth and measure the growth rate constant for the cells of Escherichia coli NBRC 3972 and Staphylococcus aureus NBRC 12732 inoculated onto an agar medium varying in nutrient concentration. The results revealed that the antimicrobial surface could prevent the division of cells either during the growth stage or before the onset of growth.

Different resistance markers (kanamycin and erythromycin) were used to construct a set of plasmids that allow expression of Staphylococcus aureus proteins fused to one of four different fluorescent proteins (FP). The developed toolbox could be used to study the localization of proteins in S. aureus, a prominent pathogen in both health care and community settings.

Discriminatory biofilm assays were used to test the efficacies of biocides representing different classes and mechanisms of action against planktonically growing Staphylococcus aureus and Pseudomonas aeruginosa. Most biocides were active only on S. aureus and P. aeruginosa biofilm cells, leaving the matrix undisturbed and only the strong oxidizers hydrogen peroxide and sodium hypochlorite which were active on both the biofilm matrix and the viable mass, make them very valuable antibiofilm agents.

New configurations of the tetracycline-dependent gene regulation (tet) system are described for Staphylococcus aureus. Tet-on control has prevailed in a configuration in which the addition of an effector has led to gene expression in control, whereas Tet-off has defined the silencing of a target gene under these conditions

Cfr9I pulsed-field gel electrophoresis (PFGE) is used on methicillin-resistance Staphylococcus aureus ST398 isolates and their PGFE profiles, protein A gene variable repeat regions (spa types) and types of the staphylococcal cassette chromosome mec (SCCmec) are compared. The combination of Cfr9I PFGE with spa and SCCmec typing has shown the heterogeneity of the series and is used for outbreak examinations and traceability studies of the MRSA ST398 emerging clone.

DNA microarray is used for identifying Staphylococcus aureus copper-responsive genes. Transcriptional analysis has shown that sae, agr, and eap are repressed under high-copper conditions and that biofilm formation is repressed under high-copper conditions.

The genomes of the two lytic mutant Staphylococcus aureus bacteriophages isolated from milk are analyzed. Comparative analysis of these bacteriophage genome structures has shown that they resemble those of [PHI]12 and [PHI]11, both representatives of large genomic within the Staphylococcus aureus-infecting phages.

The various methods adopted by the Staphylococcus aureus subpopulation for surviving in the presence of Pseudomonas aeruginosa are discussed. The analysis reveals that the selection of the small-colony variant phenotype acts as the main mechanism employed by these complexes for survival.

A combination of spa typing and multilocus sequence typing techniques is employed to analyze the different enterotoxin gene profiles observed among the clonal complexes of Staphylococcus aureus isolates. The analysis demonstrates a high frequency of the occurrence of the horizontal transfer of the mobile genetic elements within these genes.

Combinations of transcriptome and biochemical analysis were used to assess the dynamic response of Lactococcus lactis in a mixed culture with Staphylococcus aureus. The results obtained provide new insight into possible mechanisms of interaction between L. lactis and S. aureus and the unexpected effects of L. lactis on the virulence of S. aureus.

A dedicated Staphylococcus aereus microarray was developed to study the effect of Lactococcus lactis on staphylococcal gene expression in mixed cultures and establish the transcriptomic profile of S. aureus in mixed cultures with L. lactis in a chemically defined medium held at a constant pH of 6.6. The results provide insight into the complexity of L. lactis antagonistic potential for S. aureus and promising leads for nonantibiotic biocontrol of such major pathogen which is cause of numerous food poisonings.

The isolation of two novel phages designated as [Phi]SA012 and [Phi]SA039 that exhibited lytic effect on a broad range of Staphylococcus aureus isolates obtained from mastitic milk is described. The measurement obtained for optical densities during coculture with S. aureus isolates confirmed the breadth of the [Phi]SA039 host range and potent lytic capability of [Phi]SA012.

Staphylococcus aureus RN6390 has presented a diauxic growth in milk because of amino acid limitation. The inactivation of the oligopeptide permease Opp3 has not only affected the growth of the strain but also the results in reduced expression levels of three major extracellular proteases.

A truncated derivative of the phage endolysin LysK containing only the CHAP (cysteine- and histidine-dependent amidoydrolase/peptidase) domain that exhibited lytic activity against live clinical staphylococcal isolates, including methicillin-resistant Staphylococcus aureus is reported. This is the first example of truncated phage lysin that has retained high lytic activity against live staphylococcal cells.

A comparative study under flow conditions are performed to understand the adhesion and residence-time-dependent desorption of two Staphylococcus aureus strains with and without fibronectin (Fn) binding proteins (FnBPs) on Fn-coated glass. The results implied that under the mild contact conditions of convective diffusion in a flow chamber, adsorbed bovine serum albumin (BSA) prevents specific interactions but does facilitate forced Fn-FnBP binding during atomic force microscopy (AFM) or stirring in isothermal titration calorimetry (ITC).

Staphylococcus aureus and Escherichia coli are analyzed to examine the antibacterial effect and mechanism of action of an electrically generated silver ion solution. Silver ions might cause the bacteria to reach an active but nonculturable (ABNC) state and eventually die.

The DnaB intein function was altered to develop a new intein based method for generating the Staphylococcus aureus autoinducing peptides (S. aureus AIPs) signals. Results conclude that the method is simple and scalable and helps biological efforts by producing S. aureus AIPs.

The objective of a study is the identification of the best approach for determining the growth parameters based on turbidity data and use of a bioscreen instrument and characterizing variability in growth parameters of 34 Staphylococcus aureus of different biotypes isolated from broiler carcasses. Estimation of the growth parameters is done by fitting primary growth models to turbidity growth curves or detecting times of serially diluted cultures either directly or by using an analysis of variance (ANOVA) approach.

Growth media for Staphylococcus aureus strain DSM20231with VLEC is supplemented and ultramorphology, growth, and viability compared to those with unsupplemented media for prolonged culture times is determined. These data demonstrate that VLEC have profound effects on the recovery of Staphylococcus aureus even after ethanol depletion and delay the transition from primary to secondary metabolite catabolism.

The native promoter of the mycosubtilin operon from Bacillus subtilis ATCC 6633 was replaced by the repU a constitutive promoter from staphylococcus aureus plasmid pUB110. It showed that the protective effect afforded by mycosubtilin overproduction was visualized by significantly greater fresh weight of emerging seedlings treated with BBG100 compared to controls or seedlings inoculated with the wild-type strain.

Research has been conducted on C (sub)35 carotenoid biosynthetic pathway. The authors describe the construction of this pathway, and report that the pahtway has emerged when C (sub)30 carotene synthase from Staphylococcus aureus was suplied with natural substrate of C (sub)40 synthase.