Quantitative PCR analysis of genes expressed during biofilm development of methicillin resistant Staphylococcus aureus (MRSA)

Atshan, Salman Sahab; Shamsudin, Mariana Nor; Karunanidhi, Arunkumar; Belkum, Alex van; Than, Leslie Thian Lung; Nathan, Jayakayatri Jeevajothi; Ling, King-Hwa; Seng, Johnson Shueh Chong; Ali, Alreshidi Mateg; Abduljaleel, Salwa A.; Hamat, Rukman Awang

doi:10.1016/j.meegid.2013.05.002

Cited by 95 publications

(76 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Consistent with our observations, gene expression of MSCRAMMs during biofilm growth, including fnbA/B , clfa , ebps , and fib , have also been shown to be significantly enhanced during biofilm growth [23]. However, in these studies the expression of MSCRAMMs was optimally enhanced between 12 and 24 hours of biofilm growth.…”

Section: Resultssupporting

confidence: 90%

Human plasma enhances the expression of Staphylococcal microbial surface components recognizing adhesive matrix molecules promoting biofilm formation and increases antimicrobial tolerance In Vitro

et al. 2014

View full text Add to dashboard Cite

BackgroundMicrobial biofilms have been associated with the development of chronic human infections and represent a clinical challenge given their increased antimicrobial tolerance. Staphylococcus aureus is a major human pathogen causing a diverse range of diseases, of which biofilms are often involved. Staphylococcal attachment and the formation of biofilms have been shown to be facilitated by host factors that accumulate on surfaces. To better understand how host factors enhance staphylococcal biofilm formation, we evaluated the effect of whole human plasma on biofilm formation in clinical isolates of S. aureus and the expression of seven microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) known to be involved in biofilm formation by quantitative real-time PCR. We also evaluated whether plasma augmented changes in S. aureus biofilm morphology and antimicrobial resistance.ResultsExposure of clinical isolates of S. aureus to human plasma (10%) within media, and to a lesser extent when coated onto plates, significantly enhanced biofilm formation in all of the clinical isolates tested. Compared to biofilms grown under non-supplemented conditions, plasma-augmented biofilms displayed significant changes in both the biofilm phenotype and cell morphology as determined by confocal scanning laser microscopy (CLSM) and scanning electron microscopy (SEM), respectively. Exposure of bacteria to plasma resulted in a significant fold-increase in MSCRAMM expression in both a time and isolate-dependent manner. Additionally, plasma-augmented biofilms displayed an increased tolerance to vancomycin compared to biofilms grown in non-supplemented media.ConclusionsCollectively, these studies support previous findings demonstrating a role for host factors in biofilm formation and provide further insight into how plasma, a preferred growth medium for staphylococcal biofilm formation enhances as well as augments other intrinsic properties of S. aureus biofilms. Consequently, these findings indicate that incorporation of host factors may be necessary to better replicate in vivo conditions and for the best utility of a clinical biofilm assay to evaluate the process of biofilm formation and treatments.

show abstract

Section: Resultssupporting

confidence: 90%

Human plasma enhances the expression of Staphylococcal microbial surface components recognizing adhesive matrix molecules promoting biofilm formation and increases antimicrobial tolerance In Vitro

et al. 2014

View full text Add to dashboard Cite

show abstract

“…16S rRNA gene was selected as endogenous control since it was stable in its expression between control and treatment groups. Several other researchers have also used 16S rRNA gene as endogenous control for studying the expression of virulence genes in pathogens (McKillip et al, 1998; Tasara and Stephan, 2007; Xue et al, 2008; Hays, 2009; Atshan et al, 2013; Schroeder et al, 2015) including C. jejuni (Koolman et al, 2016). The flagellar biosynthesis gene, fliA regulates several genes involved in Campylobacter motility.…”

Section: Discussionmentioning

confidence: 99%

Trans-Cinnamaldehyde, Carvacrol, and Eugenol Reduce Campylobacter jejuni Colonization Factors and Expression of Virulence Genes in Vitro

et al. 2017

View full text Add to dashboard Cite

Campylobacter jejuni is a major foodborne pathogen that causes severe gastroenteritis in humans characterized by fever, diarrhea, and abdominal cramps. In the human gut, Campylobacter adheres and invades the intestinal epithelium followed by cytolethal distending toxin mediated cell death, and enteritis. Reducing the attachment and invasion of Campylobacter to intestinal epithelium and expression of its virulence factors such as motility and cytolethal distending toxin (CDT) production could potentially reduce infection in humans. This study investigated the efficacy of sub-inhibitory concentrations (SICs, concentration not inhibiting bacterial growth) of three GRAS (generally recognized as safe) status phytochemicals namely trans-cinnamaldehyde (TC; 0.005, 0.01%), carvacrol (CR; 0.001, 0.002%), and eugenol (EG; 0.005, 0.01%) in reducing the attachment, invasion, and translocation of C. jejuni on human intestinal epithelial cells (Caco-2). Additionally, the effect of these phytochemicals on Campylobacter motility and CDT production was studied using standard bioassays and gene expression analysis. All experiments had duplicate samples and were replicated three times on three strains (wild type S-8, NCTC 11168, 81–176) of C. jejuni. Data were analyzed using ANOVA with GraphPad ver. 6. Differences between the means were considered significantly different at P < 0.05. The majority of phytochemical treatments reduced C. jejuni adhesion, invasion, and translocation of Caco-2 cells (P < 0.05). In addition, the phytochemicals reduced pathogen motility and production of CDT in S-8 and NCTC 11168 (P < 0.05). Real-time quantitative PCR revealed that phytochemicals reduced the transcription of select C. jejuni genes critical for infection in humans (P < 0.05). Results suggest that TC, CR, and EG could potentially be used to control C. jejuni infection in humans.

show abstract

“…However, they appear to play larger roles in the persistence of biofilms (Atshan et al, 2013;Houston et al, 2011). They also help facilitate adherence to surfaces, as do products encoded by clfA and clfB (Götz, 2002) and ebps (Downer et al, 2002).…”

Section: Discussionmentioning

confidence: 99%

Major components of orange oil inhibit Staphylococcus aureus growth and biofilm formation, and alter its virulence factors

Federman

Christopher

Biswas

2016

Journal of Medical Microbiology

View full text Add to dashboard Cite

Bovine mastitis is a costly disease in the dairy industry and does not always respond to antibiotic treatment. The major components of terpeneless, cold-pressed Valencia orange oil -citral, linalool, decanal and valencene -were examined as potential alternative treatments for Staphylococcus aureus-associated mastitis. The minimum inhibitory concentration (MIC) of all four components against S. aureus was determined after incubation for 24 h. Growth inhibition assays were performed for all effective components on S. aureus for either a 3 h or 72 h treatment. These components were tested for the ability to disrupt pre-formed S. aureus biofilms after 24 h of treatment by measuring absorbance at 540 nm. Cytotoxicity against immortalized bovine mammary epithelial (MAC-T) cells was measured using an MTT assay following a 1 h exposure. Only concentrations below the 50 % cytostatic concentration (CC50) were used in an adherence and invasion assay of S. aureus on MAC-T cells, and for measurements of virulence and biofilm gene expression via qPCR. The MICs of citral and linalool were 0.02 % and 0.12 %, respectively, but decanal and valencene were ineffective. Citral and linalool were capable of inhibiting growth of S. aureus after 24 h at their MIC values and inhibited pre-formed biofilms of S. aureus. The concentrations below the CC50 were 0.02 % for citral and 0.12 % for linalool. These concentrations inhibited the adhesion and invasion ability of S. aureus and downregulated virulence genes. Only 0.12 % linalool downregulated the expression of S. aureus biofilm-forming genes. These components should be considered for further in vivo study.

show abstract

Quantitative PCR analysis of genes expressed during biofilm development of methicillin resistant Staphylococcus aureus (MRSA)

Cited by 95 publications

References 28 publications

Human plasma enhances the expression of Staphylococcal microbial surface components recognizing adhesive matrix molecules promoting biofilm formation and increases antimicrobial tolerance In Vitro

Human plasma enhances the expression of Staphylococcal microbial surface components recognizing adhesive matrix molecules promoting biofilm formation and increases antimicrobial tolerance In Vitro

Trans-Cinnamaldehyde, Carvacrol, and Eugenol Reduce Campylobacter jejuni Colonization Factors and Expression of Virulence Genes in Vitro

Major components of orange oil inhibit Staphylococcus aureus growth and biofilm formation, and alter its virulence factors

Contact Info

Product

Resources

About