Background: Staphylococcal protein A (SPA) is a cell wall component of Staphylococcus aureus that binds to different IgG subclasses of human and several animal species. This bacterial protein can be used as an antibody detector in various immunological assays or as an isolation reagent for the purification of antibody molecules via immuno-chromatography procedures.Objectives: Molecular cl...

Human leukocyte antigens (HLA) are gene products found in the major histocompatibility complex, aiding differentiation of “self” from “non-self” antigens, and is crucial for communication between immune cells human body. HLA-B27, specific, has a strong interrelation with different types Spondyloarthritis (SpA). The aim this study to frequency HLA-B27 suspected patients presenting axial peripher...

Protein A (SpA) of Staphylococcus aureus is endowed with the capacity to interact with the H chain variable region (V(H)) of human Abs and to target >40% of B lymphocytes. To investigate whether this property represents a virulence factor and to determine the in vivo consequences of the confrontation of SpA with B lymphocytes, we used transgenic mice expressing fully human Abs. We found that ad...

AIM The present study was undertaken to type Staphylococcus aureus isolates from cattle and buffalo mastitic milk on the basis of spa (X-region) and clfA genes, both responsible for producing virulence factors. MATERIAL AND METHODS In the present investigation S. aureus isolates were isolated as per standard protocols. Typing of S. aureus was carried out by molecular detection of spa and clfA...

OBJECTIVES To investigate the effect of subinhibitory concentrations of cell wall active antibiotics on virulence gene expression and biofilm formation in Staphylococcus aureus Newman and in laboratory strains. METHODS Promoter regions of spa, lukE and agr RNAIII were cloned upstream of a modified luxABCDE reporter. Using disc diffusion assays, the effects of antibiotics were observed on gene...

BACKGROUND AND OBJECTIVES Methicillin Resistant Staphylococcus aureus (MRSA) strains are divided into Community Associated (CA-) and Hospital Associated (HA-) MRSA. These strains vary in antimicrobial resistance and pathogenicity. S. aureus is one of the most common microorganisms in ocular infections. This study was aimed to determine antimicrobial resistance patterns and genetic characteristi...

When exploring biological determinants of spontaneous physical activity (SPA), it is critical to consider whether methodological factors differentially affect rodents and the measured SPA. We determined whether acclimation time, sensory stimulation, vendor, or chamber size affected measures in rodents with varying propensity for SPA. We used principal component analysis to determine which SPA c...

Staphylococcus aureus is a gram-positive pathogen that is capable of expressing a variety of virulence proteins in response to environmental signals. Virulence protein expression in S. aureus is controlled by a network of regulatory loci including sarA and agr. The sarA/agr network is associated with the expression of cell wall-associated adhesins during exponential growth and the expression of...

Staphylococcus aureus RNAIII is one of the largest regulatory RNAs, which controls several virulence genes encoding exoproteins and cell-wall-associated proteins. One of the RNAIII effects is the repression of spa gene (coding for the surface protein A) expression. Here, we show that spa repression occurs not only at the transcriptional level but also by RNAIII-mediated inhibition of translatio...

The production of the type I antimicrobial peptide (AMP) subtilin by Bacillus subtilis is regulated in a cell-density-dependent manner [Kleerebezem M, de Vos WM, Kuipers OP. The lantibiotics nisin and subtilin act as extracellular regulators of their own biosynthesis. In: Dunny GM, Winans SC, editors. Cell-cell signaling in bacteria. Washington, D.C., USA: ASM Press; 1999. p. 159-74; Stein T, B...