introduction: biofilm producing staphylococcus aureus is known as one of the major causative agents of infections, failure of implanted devices and persistent infection among hospitalized patients . the aim of the present study was to determine the frequency of biofilm producing s. aureus isolates amongst the clinical specimens. methods: this cross-sectional study was conducted during 2012 to 2...

In Bacillus subtilis, Spx was recently characterized as a novel type of global regulator whose activity is regulated by the redox status of the cells. In the present study, we demonstrate that inactivation of Spx in the important pathogen Staphylococcus aureus renders the cells hypersensitive to a wide range of stress conditions including high and low temperature, high osmolarity, and hydrogen ...

Background and Objective: Uropathogenic Escherichia coli (UPEC) are the most common cause of urinary tract infections. The binding of these bacteria to epithelial cells and the formation of biofilms cause these bacteria to be further colonized and difficult to remove in the urinary tract. This study aimed to determine the antibiotic resistance and to evaluate the biofilm formation power in Esch...

The icaADBC gene was first identified in Staphylococcus epidermidis, and is also present in Staphylococcus aureus and other Staphylococcal species. PIA is produced by the gene products encoded by the icaADBC operon. Asymptomatically colonized patients and health care workers are the major sources of MRSA in the hospital environment. MRSA-infected patients in burns units are particularly problem...

Klebsiella pneumoniae type 3 fimbriae are encoded by mrkABCDF genes which produce the major pilin subunit MrkA, chaperone MrkB, outer membrane usher MrkC, adhesin MrkD and MrkF of unknown function, respectively. RT-PCR analysis demonstrated that the mrkF gene is contained within the mrk operon. Deletion of mrkF in K. pneumoniae CG43 was found to reduce biofilm formation. A higher level of biofi...

We tell of a journey that led to discovery of amyloids formed by yeast cell adhesins and their importance in biofilms and host immunity. We begin with the identification of the adhesin functional amyloid-forming sequences that mediate fiber formation in vitro. Atomic force microscopy and confocal microscopy show 2-dimensional amyloid "nanodomains" on the surface of cells that are activated for ...

The hospital environment microflora comprise a wide variety of microorganisms which are more or less pathogenic and where staphylococci are one of the most common types. The aim of the presented study was to evaluate the prevalence of the biofilm forming coagulase-negative staphylococci (CoNS) in a hospital environment as a risk factor for nosocomial infections. Among 122 isolated and tested st...

Nosocomial infections caused by Staphylococcus epidermidis are characterized by biofilm formation on implanted medical devices. Quorum-sensing regulation plays a major role in the biofilm development of many bacterial pathogens. Here, we describe luxS, a quorum-sensing system in staphylococci that has a significant impact on biofilm development and virulence. We constructed an isogenic Deltalux...

Escherichia coli is the primary cause of urinary tract infection (UTI) in the developed world. The major factors associated with the virulence of uropathogenic E. coli (UPEC) are fimbrial adhesins, which mediate specific attachment to host receptors and trigger innate host responses. Another group of adhesins is represented by the autotransporter subgroup of proteins. The best characterized of ...