scholarly journals Global Gene Expression in Staphylococcus aureus Biofilms

2004 ◽  
Vol 186 (14) ◽  
pp. 4665-4684 ◽  
Author(s):  
Karen E. Beenken ◽  
Paul M. Dunman ◽  
Fionnuala McAleese ◽  
Daphne Macapagal ◽  
Ellen Murphy ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Adaptive Response ◽  
Biofilm Formation ◽  
Global Gene Expression ◽  
Growth Conditions ◽  
Anaerobic Growth ◽  
Over Expression ◽  
Custom Made

ABSTRACT We previously demonstrated that mutation of the staphylococcal accessory regulator (sarA) in a clinical isolate of Staphylococcus aureus (UAMS-1) results in an impaired capacity to form a biofilm in vitro (K. E. Beenken, J. S. Blevins, and M. S. Smeltzer, Infect. Immun. 71:4206-4211, 2003). In this report, we used a murine model of catheter-based biofilm formation to demonstrate that a UAMS-1 sarA mutant also has a reduced capacity to form a biofilm in vivo. Surprisingly, mutation of the UAMS-1 ica locus had little impact on biofilm formation in vitro or in vivo. In an effort to identify additional loci that might be relevant to biofilm formation and/or the adaptive response required for persistence of S. aureus within a biofilm, we isolated total cellular RNA from UAMS-1 harvested from a biofilm grown in a flow cell and compared the transcriptional profile of this RNA to RNA isolated from both exponential- and stationary-phase planktonic cultures. Comparisons were done using a custom-made Affymetrix GeneChip representing the genomic complement of six strains of S. aureus (COL, N315, Mu50, NCTC 8325, EMRSA-16 [strain 252], and MSSA-476). The results confirm that the sessile lifestyle associated with persistence within a biofilm is distinct by comparison to the lifestyles of both the exponential and postexponential phases of planktonic culture. Indeed, we identified 48 genes in which expression was induced at least twofold in biofilms over expression under both planktonic conditions. Similarly, we identified 84 genes in which expression was repressed by a factor of at least 2 compared to expression under both planktonic conditions. A primary theme that emerged from the analysis of these genes is that persistence within a biofilm requires an adaptive response that limits the deleterious effects of the reduced pH associated with anaerobic growth conditions.

scholarly journals Anaerobic Conditions Induce Expression of Polysaccharide Intercellular Adhesin in Staphylococcus aureus and Staphylococcus epidermidis

2001 ◽  
Vol 69 (6) ◽  
pp. 4079-4085 ◽  
Author(s):  
Sarah E. Cramton ◽  
Martina Ulrich ◽  
Friedrich Götz ◽  
Gerd Döring
Keyword(s):  
Staphylococcus Aureus ◽  
Staphylococcus Epidermidis ◽  
Biofilm Formation ◽  
Extracellular Polysaccharide ◽  
Growth Conditions ◽  
Anaerobic Conditions ◽  
Anaerobic Environment ◽  
Specific Mrna

ABSTRACT Products of the intercellular adhesion (ica) operon in Staphylococcus aureus and Staphylococcus epidermidis synthesize a linear β-1,6-linked glucosaminylglycan. This extracellular polysaccharide mediates bacterial cell-cell adhesion and is required for biofilm formation, which is thought to increase the virulence of both pathogens in association with prosthetic biomedical implants. The environmental signal(s) that triggers ica gene product and polysaccharide expression is unknown. Here we demonstrate that anaerobic in vitro growth conditions lead to increased polysaccharide expression in both S. aureus and S. epidermidis, although the regulation is less stringent inS. epidermidis. Anaerobiosis also dramatically stimulates ica-specific mRNA expression inica- and polysaccharide-positive strains of both S. aureus and S. epidermidis.These data suggest a mechanism whereby ica gene expression and polysaccharide production may act as a virulence factor in an anaerobic environment in vivo.

scholarly journals Iron-Regulated Biofilm Formation in Staphylococcus aureus Newman Requires ica and the Secreted Protein Emp

2008 ◽  
Vol 76 (4) ◽  
pp. 1756-1765 ◽  
Author(s):  
Miranda Johnson ◽  
Alan Cockayne ◽  
Julie A. Morrissey
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Surface ◽  
Biofilm Formation ◽  
Growth Conditions ◽  
Secreted Proteins ◽  
Iron Regulation ◽  
Secreted Protein ◽  
Virulence Determinants

ABSTRACT Staphylococcus aureus biofilm formation is induced in iron-restricted growth conditions in vitro. In this study, we showed that Emp and Eap play important roles in low-iron-induced biofilm formation of S. aureus Newman. Eap and Emp are secreted proteins which are non-covalently attached to the S. aureus cell surface and have previously been implicated in a number of aspects of S. aureus pathogenesis. We showed here that the transcription of these important virulence factors is induced by growth in low-iron medium, reflective of the in vivo environment. Our results show that iron regulation of Eap and Emp is Fur independent. However, Fur is required for full induction of eap and emp expression in low-iron conditions. In this study, we demonstrated that in addition to Fur, low-iron-induced biofilm formation requires Sae, Agr, and SarA. In iron-restricted growth conditions, Sae and Agr are essential for Emp and Eap expression and hence for biofilm formation, whereas SarA appears to have a less-significant role. We also showed that expression of the ica operon is required for biofilm formation in iron-restricted growth conditions. We demonstrated that in fact, ica is required for the expression of the important multifunctional virulence determinants eap and emp.

scholarly journals Evaluation of Antibiotics Active against Methicillin-Resistant Staphylococcus aureus Based on Activity in an Established Biofilm

2016 ◽  
Vol 60 (10) ◽  
pp. 5688-5694 ◽  
Author(s):  
Daniel G. Meeker ◽  
Karen E. Beenken ◽  
Weston B. Mills ◽  
Allister J. Loughran ◽  
Horace J. Spencer ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Biofilm Formation ◽  
Limit Of Detection ◽  
Relative Activity ◽  
Methicillin Resistant ◽  
Content Type ◽  
Comparable Activity ◽  
Antibiotic Delivery

ABSTRACTWe usedin vitroandin vivomodels of catheter-associated biofilm formation to compare the relative activity of antibiotics effective against methicillin-resistantStaphylococcus aureus(MRSA) in the specific context of an established biofilm. The results demonstrated that, underin vitroconditions, daptomycin and ceftaroline exhibited comparable activity relative to each other and greater activity than vancomycin, telavancin, oritavancin, dalbavancin, or tigecycline. This was true when assessed using established biofilms formed by the USA300 methicillin-resistant strain LAC and the USA200 methicillin-sensitive strain UAMS-1. Oxacillin exhibited greater activity against UAMS-1 than LAC, as would be expected, since LAC is an MRSA strain. However, the activity of oxacillin was less than that of daptomycin and ceftaroline even against UAMS-1. Among the lipoglycopeptides, telavancin exhibited the greatest overall activity. Specifically, telavancin exhibited greater activity than oritavancin or dalbavancin when tested against biofilms formed by LAC and was the only lipoglycopeptide capable of reducing the number of viable bacteria below the limit of detection. With biofilms formed by UAMS-1, telavancin and dalbavancin exhibited comparable activity relative to each other and greater activity than oritavancin. Importantly, ceftaroline was the only antibiotic that exhibited greater activity than vancomycin when testedin vivoin a murine model of catheter-associated biofilm formation. These results emphasize the need to consider antibiotics other than vancomycin, most notably, ceftaroline, for the treatment of biofilm-associatedS. aureusinfections, including by the matrix-based antibiotic delivery methods often employed for local antibiotic delivery in the treatment of these infections.

scholarly journals Tissue Plasminogen Activator Coating on Implant Surfaces Reduces Staphylococcus aureus Biofilm Formation

2015 ◽  
Vol 82 (1) ◽  
pp. 394-401 ◽  
Author(s):  
Jakub Kwiecinski ◽  
Manli Na ◽  
Anders Jarneborn ◽  
Gunnar Jacobsson ◽  
Marijke Peetermans ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Plasminogen Activator ◽  
Tissue Plasminogen Activator ◽  
Medical Devices ◽  
Biofilm Formation ◽  
Bacterial Biofilm ◽  
Content Type ◽  
Tissue Plasminogen

ABSTRACTStaphylococcus aureusbiofilm infections of indwelling medical devices are a major medical challenge because of their high prevalence and antibiotic resistance. As fibrin plays an important role inS. aureusbiofilm formation, we hypothesize that coating of the implant surface with fibrinolytic agents can be used as a new method of antibiofilm prophylaxis. The effect of tissue plasminogen activator (tPA) coating onS. aureusbiofilm formation was tested within vitromicroplate biofilm assays and anin vivomouse model of biofilm infection. tPA coating efficiently inhibited biofilm formation by variousS. aureusstrains. The effect was dependent on plasminogen activation by tPA, leading to subsequent local fibrin cleavage. A tPA coating on implant surfaces prevented both early adhesion and later biomass accumulation. Furthermore, tPA coating increased the susceptibility of biofilm infections to antibiotics.In vivo, significantly fewer bacteria were detected on the surfaces of implants coated with tPA than on control implants from mice treated with cloxacillin. Fibrinolytic coatings (e.g., with tPA) reduceS. aureusbiofilm formation bothin vitroandin vivo, suggesting a novel way to prevent bacterial biofilm infections of indwelling medical devices.

scholarly journals Oral Administration of the Broad-Spectrum Antibiofilm Compound Toremifene Inhibits Candida albicans and Staphylococcus aureus Biofilm FormationIn Vivo

2014 ◽  
Vol 58 (12) ◽  
pp. 7606-7610 ◽  
Author(s):  
Kaat De Cremer ◽  
Nicolas Delattin ◽  
Katrijn De Brucker ◽  
Annelies Peeters ◽  
Soña Kucharíková ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Candida Albicans ◽  
Broad Spectrum ◽  
Staphylococcus Epidermidis ◽  
Biofilm Formation ◽  
Candida Krusei ◽  
Content Type ◽  
And Staphylococcus Aureus

ABSTRACTWe here report on thein vitroactivity of toremifene to inhibit biofilm formation of different fungal and bacterial pathogens, includingCandida albicans,Candida glabrata,Candida dubliniensis,Candida krusei,Pseudomonas aeruginosa,Staphylococcus aureus, andStaphylococcus epidermidis. We validated thein vivoefficacy of orally administered toremifene againstC. albicans and S. aureusbiofilm formation in a rat subcutaneous catheter model. Combined, our results demonstrate the potential of toremifene as a broad-spectrum oral antibiofilm compound.

scholarly journals Bacillus subtilis YngB is a UTP-glucose-1-phosphate uridylyltransferase contributing to wall teichoic acid modification and glycolipid formation during anaerobic growth

2020 ◽  
Author(s):  
Chih-Hung Wu ◽  
Jeanine Rismondo ◽  
Rhodri M. L. Morgan ◽  
Yang Shen ◽  
Martin J. Loessner ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Teichoic Acid ◽  
Glucose Production ◽  
Growth Conditions ◽  
Anaerobic Growth ◽  
Acid Modification ◽  
Wall Teichoic Acid ◽  
Native Promoter

AbstractUTP-glucose-1-phosphate uridylyltransferases (UGPases) are enzymes that produce UDP-glucose from UTP and glucose-1-phosphate. In Bacillus subtilis 168, UDP-glucose is required for the decoration of wall teichoic acid (WTA) with glucose residues and the formation of glucolipids. The B. subtilis UGPase GtaB is essential for UDP-glucose production under standard aerobic growth conditions, and gtaB mutants display severe growth and morphological defects. However, bioinformatics predictions indicate that two other UGPases, are present in B. subtilis. Here, we investigated the function of one of them named YngB. The crystal structure of YngB revealed that the protein has the typical fold and all necessary active site features of a functional UGPase. Furthermore, UGPase activity could be demonstrated in vitro using UTP and glucose-1-phosphate as substrates. Expression of YngB from a synthetic promoter in a B. subtilis gtaB mutant resulted in the reintroduction of glucose residues on WTA and production of glycolipids, demonstrating that the enzyme can function as UGPase in vivo. When wild-type and mutant B. subtilis strains were grown under anaerobic conditions, YngB-dependent glycolipid production and glucose decorations on WTA could be detected, revealing that YngB is expressed from its native promoter under anaerobic condition. Based on these findings, along with the structure of the operon containing yngB and the transcription factor thought to be required for its expression, we propose that besides WTA, potentially other cell wall components might be decorated with glucose residues during oxygen limited growth condition.

Biosurfactants of Lactobacillus helveticus for biodiversity inhibit the biofilm formation of Staphylococcus aureus and cell invasion

2019 ◽  
Vol 14 (13) ◽  
pp. 1133-1146 ◽  
Author(s):  
Xinpeng Jiang ◽  
Xin Yan ◽  
Shanshan Gu ◽  
Yan Yang ◽  
Lili Zhao ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Host Cell ◽  
Biofilm Formation ◽  
Lactobacillus Helveticus ◽  
Real Time Quantitative Pcr ◽  
Autoinducer 2 ◽  
New Strategy ◽  
Better Than

Aim: This study aimed to evaluate the differences of biosurfactants produced by two Lactobacillus helveticus strains against the biofilm formation of Staphylococcus aureus in vitro and in vivo. Materials & methods: Scanning electron microscopy, Real time-quantitative PCR (RT-qPCR) and cell assay were used to analyze the inhibiting effect of biosurfactants against biofilm formation. Results & conclusion: Results showed that the biosurfactants have anti-adhesive and inhibiting effects on biofilm formation in vivo and in vitro. The biofilm-formative genes and autoinducer-2 signaling regulated these characteristics, and the biosurfactant L. helveticus 27170 is better than that of 27058. Host cell adhesion and invasion results indicated that the biosurfactants L. helveticus prevented the S. aureus invading the host cell, which may be a new strategy to eliminate biofilms.

scholarly journals Adaptive response of vascular endothelial cells to an acute increase in shear stress magnitude

2012 ◽  
Vol 302 (4) ◽  
pp. H983-H991 ◽  
Author(s):  
Ji Zhang ◽  
Morton H. Friedman
Keyword(s):  
Endothelial Cells ◽  
Shear Stress ◽  
Adaptive Response ◽  
Vascular Endothelial Cells ◽  
Endothelial Permeability ◽  
Global Gene Expression ◽  
Vascular Endothelial ◽  
Acute Increase

The adaptation of vascular endothelial cells to shear stress alteration induced by global hemodynamic changes, such as those accompanying exercise or digestion, is an essential component of normal endothelial physiology in vivo. An understanding of the transient regulation of endothelial phenotype during adaptation to changes in mural shear will advance our understanding of endothelial biology and may yield new insights into the mechanism of atherogenesis. In this study, we characterized the adaptive response of arterial endothelial cells to an acute increase in shear stress magnitude in well-defined in vitro settings. Porcine endothelial cells were preconditioned by a basal level shear stress of 15 ± 15 dyn/cm2 at 1 Hz for 24 h, after which an acute increase in shear stress to 30 ± 15 dyn/cm2 was applied. Endothelial permeability nearly doubled after 40-min exposure to the elevated shear stress and then decreased gradually. Transcriptomics studies using microarray techniques identified 86 genes that were sensitive to the elevated shear. The acute increase in shear stress promoted the expression of a group of anti-inflammatory and antioxidative genes. The adaptive response of the global gene expression profile is triphasic, consisting of an induction period, an early adaptive response (ca. 45 min) and a late remodeling response. Our results suggest that endothelial cells exhibit a specific phenotype during the adaptive response to changes in shear stress; this phenotype is different than that of fully adapted endothelial cells.

Sign in / Sign up

Export Citation Format

Share Document