Optimization of a protocol for gene expression using biofilm cells from S. epid...

Gene expression assays are one of the most common tools used nowadays to evaluate the importance of genes in many different life sciences areas, namely, in clinical microbiology. Since most gene expression kits for qPCR have been optimized for assays with planktonic cells it is important to also optimize protocols for this type of assays, to be used with biofilms. Biofilms are communities of bacteria that grow ...

Staphylococcus epidermidis biofilms with higher proportions of dormant bacteria...

Staphylococcus epidermidis an opportunistic pathogen due to its ability to establish biofilms on indwelling medical devices. The presence of high amounts of dormant bacteria is a hallmark of biofilms, making them more tolerant to antimicrobials and to the host immune response. We observed that S. epidermidis biofilms grown in excess glucose accumulated high amounts of viable but non-culturable (VBNC) bacteria, ...

Comparison of RNA extraction methods from biofilm samples of Staphylococcus epi...

BACKGROUND: Microbial biofilms are communities of bacteria adhered to a surface and surrounded by an extracellular polymeric matrix. Biofilms have been associated with increased antibiotic resistance and tolerance to the immune system. Staphylococcus epidermidis is the major bacterial species found in biofilm-related infections on indwelling medical devices. Obtaining high quality mRNA from biofilms is crucial ...

Staphylococcus epidermidis biofilm dispersal cells : an intermediary phenotype?

Optimizing a qPCR gene expression quantification assay for S. epidermidis biofi...

Staphylococcus epidermidis biofilm-related infections are a current concern within the medical community due to their high incidence and prevalence, particularly in patients with indwelling medical devices. Biofilm gene expression analysis by quantitative real-time PCR (qPCR) has been increasingly used to understand the role of biofilm formation in the pathogenesis of S. epidermidis infections. However, dependi...

Monoclonal antibody raised against PNAG has variable effects on static S. epide...

This work was funded by FEDER funds through the Operational Programme for Competitiveness Factors – COMPETE and by National Funds through FCT – Foundation for Science and Technology under the project Pest-C/ EQB/LA0006/2013. C. S. and F. G. were supported by post-doctoral grants from Fundação para a Ciência e a Tecnologia (SFRH/BPD/70548/2010 and SFRH/BPD/95556/2013, respectively).

Antibiotic resistance and biofilm formation ability among coagulase-negative st...

In the past few years the interest in coagulase-negative staphylococci (CoNS) species has significantly increased due to their impact on human health and disease. CoNS are common bacterial colonizers of the normal human microflora and usually have a benign relationship with the host.; This work was funded by Fundacao para a Ciencia e a Tecnologia (FCT) and COMPETE grants PTDC/BIA-MIC/113450/2009 and FCOMP-01-01...

Lysis buffer properties: influence on S. epidermidis biofilm proteome analysis

Besides being part of human commensal flora, S. epidermidis has the ability to colonize and form biofilms in artificial implants. Due to the particular characteristics of biofilms, conventional methods used to disrupt and lyses biofilms from Gram positive bacteria may include association between mechanical, enzymatic and chemical methods. Nevertheless, proteomic characterization is highly dependent of the extra...

Controlled RNA contamination and degradation and its impact on qPCR gene expres...

RNA quality is of utmost importance to perform gene expression quantification by qPCR. The classical methods used to determine \RNA\ quality are based on electrophoresis and spectrophotometer assessment, namely A260/A280 and A260/A230 ratios. It was previously shown that due to the complex nature of Staphylococcus epidermidis biofilms, \RNA\ extraction procedures could impact mRNA quality and thus accurate quan...

Dormancy within Staphylococcus epidermidis biofilms : a transcriptomic analysis...

The proportion of dormant bacteria within Staphylococcus epidermidis biofilms may determine its inflammatory profile. Previously, we have shown that S. epidermidis biofilms with higher proportions of dormant bacteria have reduced activation of murine macrophages. RNA-sequencing was used to identify the major transcriptomic differences between S. epidermidis biofilms with different proportions of dormant bacteri...