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Staphylococcal biofilm

Louise Kruse Jensen, Nicole Lind Henriksen, Thomas Bjarnsholt, Kasper Nørskov Kragh, Henrik Elvang Jensen
Aim: Visualization of Staphylococcus aureus biofilm using histochemical staining and combined histochemistry (HC) and immunohistochemistry (IHC). Methods: The ability of S. aureus S54F9 to form biofilm was tested in vitro . Hereafter, infected bone tissue was collected from two different porcine models of osteomyelitis inoculated with S. aureus strain S54F9. The infection time was five and fifteen days, respectively. Twenty-five different histochemical staining protocols were tested in order to find the stains that could identify extracellular biofilm matrix...
2018: Journal of Bone and Joint Infection
Olivier Poupel, Caroline Proux, Bernd Jagla, Tarek Msadek, Sarah Dubrac
The success of Staphylococcus aureus, as both a human and animal pathogen, stems from its ability to rapidly adapt to a wide spectrum of environmental conditions. Two-component systems (TCSs) play a crucial role in this process. Here, we describe a novel staphylococcal virulence factor, SpdC, an Abi-domain protein, involved in signal sensing and/or transduction. We have uncovered a functional link between the WalKR essential TCS and the SpdC Abi membrane protein. Expression of spdC is positively regulated by the WalKR system and, in turn, SpdC negatively controls WalKR regulon genes, effectively constituting a negative feedback loop...
March 2018: PLoS Pathogens
Anna Bielenica, Aleksandra Drzewiecka-Antonik, Paweł Rejmak, Joanna Stefańska, Michał Koliński, Sebastian Kmiecik, Bogdan Lesyng, Marta Włodarczyk, Piotr Pietrzyk, Marta Struga
A series of Cu(II) complexes of 3-(trifluoromethyl)phenylthiourea derivatives was synthesized. Their structural properties were investigated by spectroscopic techniques (infrared and electron paramagnetic resonance), as well as molecular modeling. All studied coordination compounds are mononuclear complexes containing two chelating ligands bonded to the metal cation via S and deprotonated N atoms. The new chelates were evaluated for their antimicrobial potency. The complex of 1-(3,4-dichlorophenyl)-3-[3-(trifluoromethyl)phenyl]thiourea (3) presented the highest activity against Gram-positive pathogens, even stronger than the activity of its non-complexed counterpart and the reference drug...
January 16, 2018: Journal of Inorganic Biochemistry
Inês Santos Ferreira, Judith Kikhney, Laura Kursawe, Stefanie Kasper, Lídia M D Gonçalves, Andrej Trampuz, Annette Moter, Ana Francisca Bettencourt, António J Almeida
Eradication of Gram-positive biofilms is a critical aspect in implant-associated infection treatment. Although antibiotic-containing particulate carriers may be a promising strategy for overcoming biofilm tolerance, the assessment of their interaction with biofilms has not been fully explored. In the present work, the antibiofilm activity of daptomycin- and vancomycin-loaded poly(methyl methacrylate) (PMMA) and PMMA-Eudragit RL 100 (EUD) microparticles against methicillin-resistant Staphylococcus aureus (MRSA) and polysaccharide intercellular adhesin-positive S...
February 27, 2018: AAPS PharmSciTech
Zulfiqar Ali Mirani, Muhammad Naseem Khan, Anila Siddiqui, Fouzia Khan, Mubashir Aziz, Shagufta Naz, Ayaz Ahmed, Seema Ismat Khan
Objectives: Staphylococcus aureus is a Gram-positive pathogen, well known for its resistance and versatile lifestyle. Under unfavourable conditions, it adapts biofilm mode of growth. For staphylococcal biofilm formation, production of extracellular polymeric substances (EPS) is a pre-requisite, which is regulated by ica operon-encoded enzymes. This study was designed to know the impact of ascorbic acid on biofilm formation and colony spreading processes of S. aureus and MRSA. Materials and Methods: The isolates of methicillin-resistant S...
February 2018: Iranian Journal of Basic Medical Sciences
Pierre Delpech, Muna ALeryan, Brian Jones, Curtis Gemmell, Sue Lang
Skin and soft tissue infections (SSTI) are among the most commonly occurring infections and evidence suggests that these are increasing world-wide. The aetiology is diverse, but Staphylococcus aureus predominate and these are often resistant to antimicrobials that were previously effective. Tedizolid is a new oxazolidinone-class antibacterial indicated for the treatment of adults with SSTI caused by Gram-positive pathogens, including S. aureus. The aim of this study was to evaluate the in vitro efficacy of tedizolid in comparison to other clinically used antibacterials against antibiotic sensitive- and resistant-staphylococci, grown in planktonic cultures and as biofilms reflecting the growth of the microorganism during episodes of SSTI...
January 10, 2018: Diagnostic Microbiology and Infectious Disease
Sai Nithya, T R Nimal, Gaurav Baranwal, Maneesha K Suresh, Anuj C P, V Anil Kumar, C Gopi Mohan, R Jayakumar, Raja Biswas
Lysostaphin (LST) is a bacteriocin that cleaves within the pentaglycine cross bridge of Staphylococcus aureus peptidoglycan. Previous studies have reported the high efficiency of LST even against multi drug resistant S. aureus including methicillin resistant S. aureus (MRSA). In this study, we have developed a new chitosan based hydrogel formulation of LST to exploit its anti-staphylococcal activity. The atomic interactions of LST with chitosan were studied by molecular docking studies. The rheology and the antibacterial properties of the developed LSTC gel were evaluated...
February 2, 2018: International Journal of Biological Macromolecules
Huda Saber, Azmiza Syawani Jasni, Tengku Zetty Maztura Tengku Jamaluddin, Rosni Ibrahim
Coagulase-negative staphylococci (CoNS) are considered low pathogenic organisms. However, they are progressively causing more serious infections with time because they have adapted well to various antibiotics owing to their ability to form biofilms. Few studies have been conducted on CoNS in both, hospital and community-acquired settings, especially in Malaysia. Thus, it is important to study their species and gene distributions. A mobile genetic element, staphylococcal cassette chromosome mec (SCCmec), plays an important role in staphylococci pathogenesis...
October 2017: Malaysian Journal of Medical Sciences: MJMS
Katarzyna Grecka, Piotr M Kuś, Randy W Worobo, Piotr Szweda
The antimicrobial activity of 144 samples of honeys including 95 products from apiaries located in Northern Poland was evaluated. The antibacterial activity of those natural products, their thermal stability, and activity in the presence of catalase was investigated by microdilution assays in titration plates. The MTT assay was performed for the determination of anti-biofilm activity. Spectrophotometric assays were used for the determination of antioxidant potential, total phenolic content, and ability to generate hydrogen peroxide...
January 28, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Cristina El Haj, Oscar Murillo, Alba Ribera, Nuria Lloberas, Joan Gómez-Junyent, Fe Tubau, Pere Fontova, Carme Cabellos, Javier Ariza
BACKGROUND: Linezolid or cotrimoxazole plus rifampicin (RIF) are alternative oral treatments for staphylococcal prosthetic joint infections when fluoroquinolones are not possible to use, but there is limited evidence about its activity. OBJECTIVES: We evaluated the efficacy of linezolid (LZD) and cotrimoxazole (SXT) alone and in combination with RIF against Staphylococcus aureus in an in vitro pharmacokinetic/pharmacodynamic biofilm model. METHODS: Using the CDC Biofilm Reactor® system, simulated regimens of LZD (600 mg q12h), SXT (160/800 mg q8h) and levofloxacin (LVX, 750 mg/day) alone and in combination with RIF (600 mg/day) were evaluated against one MSSA and one MRSA strain...
January 25, 2018: International Journal of Antimicrobial Agents
Eric G Romanowski, Nicholas A Stella, Kathleen A Yates, Kimberly M Brothers, Regis P Kowalski, Robert M Q Shanks
OBJECTIVES: The purpose of this study was to determine whether a commercial formulation of hypochlorous acid hygiene solution (0.01%), Avenova, can destroy existing biofilms formed by ocular clinical bacterial isolates, including blepharitis isolates of Staphylococcus aureus and coagulase-negative staphylococci, and a keratitis isolate of Pseudomonas aeruginosa. METHODS: Biofilms grown in bacterial growth media on disposable contact lens cases were challenged with hypochlorous acid hygiene solution...
January 15, 2018: Eye & Contact Lens
Zhaojun Zheng, Qingzhong Liu, Wooseong Kim, Nagendran Tharmalingam, Beth Burgwyn Fuchs, Eleftherios Mylonakis
AIM:  Staphylococcus aureus is a major cause of severe hospital-acquired infections, and biofilm formation is an important part of staphylococcal pathogenesis. Therefore, developing new antimicrobial agents against both planktonic cells and biofilm of S. aureus is a major challenge. RESULTS: Three 1,3,4-oxadiazole derivatives exhibited antimicrobial activity against seven S. aureus strains in vitro, with minimum inhibitory concentrations ranging from 4 to 32 μg/ml...
January 15, 2018: Future Medicinal Chemistry
Grith M M Hermansen, Pavelas Sazinas, Ditte Kofod, Andrew Millard, Paal Skytt Andersen, Lars Jelsbak
Interspecies interactions between bacterial pathogens and the commensal microbiota can influence disease outcome. In the nasal cavities, Staphylococcus epidermidis has been shown to be a determining factor for Staphylococcus aureus colonization and biofilm formation. However, the interaction between S. epidermidis and S. aureus has mainly been described by phenotypic analysis, and little is known about how this interaction modulates gene expression.This study aimed to determine the interactome of nasal S. aureus and S...
January 9, 2018: FEMS Microbiology Letters
Jérôme Josse, Frédéric Laurent, Alan Diot
Opportunistic bacteria from the genus Staphylococcus can cause life-threatening infections such as pneumonia, endocarditis, bone and joint infections, and sepsis. This pathogenicity is closely related to their capacity to bind directly to the extracellular matrix or to host cells. Adhesion is indeed the first step in the formation of biofilm or the invasion of host cells, which protect the bacteria from the host immune system and facilitate chronic infection. Adhesion relies on the expression of a repertoire of surface proteins called adhesins, notably microbial surface components recognizing adhesive matrix molecules...
2017: Frontiers in Microbiology
Bishakh Rout, Chi-Hsien Liu, Wei-Chi Wu
BACKGROUND: Photodynamic therapy has been studied by many studies as a method for inactivating bacterial growth. Workers have used planktonic bacterial as well as biofilm bacterial cultures to evaluate the potential of photodynamic therapy in inactivating bacteria. However, almost all the studies use a photosensitiser in aqueous solution, which could be detrimental to the efficiency of photodynamic therapy. METHODS: In this study, the photodynamic killing effect of toluidine blue O (TBO) has been investigated on Staphylococcal biofilms in -vitro...
December 13, 2017: Photodiagnosis and Photodynamic Therapy
Li-Chong Xu, Zhongjing Li, Zhicheng Tian, Chen Chen, Harry R Allcock, Christopher A Siedlecki
A new poly[bis(octafluoropentoxy) phosphazene] (OFP) was synthesized for the purpose of blood contacting medical devices. OFP was further either developed into crosslinkable polyphosphazene (X-OFP) or blended with polyurethane (PU) as the mixture (OFP/PU) for improvement of mechanical property of polyphosphazene polymers. All the materials were fabricated as smooth films or further textured with submicron pillars for the assay of antimicrobial and antithrombotic properties. Results showed that crosslinkable OFP (X-OFP) and blends of OFP/PU successfully improved the mechanical strength of OFP and fewer defects of pillars were found on the textured polyphosphazene surfaces...
February 2018: Acta Biomaterialia
Irshad S Sharafutdinov, Elena Y Trizna, Diana R Baidamshina, Maria N Ryzhikova, Regina R Sibgatullina, Alsu M Khabibrakhmanova, Liliya Z Latypova, Almira R Kurbangalieva, Elvira V Rozhina, Mareike Klinger-Strobel, Rawil F Fakhrullin, Mathias W Pletz, Mikhail I Bogachev, Airat R Kayumov, Oliwia Makarewicz
The gram-positive opportunistic bacterium Staphylococcus aureus is one of the most common causatives of a variety of diseases including skin and skin structure infection or nosocomial catheter-associated infections. The biofilm formation that is an important virulence factor of this microorganism renders the antibiotic therapy ineffective, because biofilm-embedded bacteria exhibit strongly increased tolerance to antimicrobials. Here, we describe a novel 3-chloro-5( S )-[(1 R ,2 S ,5 R )-2-isopropyl-5-methylcyclohexyloxy]-4-[4-methylphenylsulfonyl]-2(5 H )-furanone ( F105 ), possessing a sulfonyl group and l -menthol moiety...
2017: Frontiers in Microbiology
S Hogan, J P O'Gara, E O'Neill
Staphylococcal infections involving biofilms represent a significant challenge in the treatment of patients with device-related infections. Staphylococcus aureus biofilms have been shown to be SaeRS regulated and dependent on the coagulase-catalyzed conversion of fibrinogen into fibrin on surfaces coated with human plasma. Here we investigated the treatment of staphylococcal biofilm device-related infections by digesting the fibrin biofilm matrix with and without existing antimicrobials. The fibrinolytic agents plasmin, streptokinase, and nattokinase, and TrypLE, a recombinant trypsin-like protease, were used to digest and treat S...
February 2018: Antimicrobial Agents and Chemotherapy
Minh-Thu Nguyen, Arif Luqman, Katharina Bitschar, Tobias Hertlein, Johannes Dick, Knut Ohlsen, Barbara Bröker, Birgit Schittek, Friedrich Götz
Most Staphylococcus aureus strains secrete two lipases SAL1 and SAL2 encoded by gehA and gehB. These two lipases differ with respect to their substrate specificity. Staphylococcus hyicus secretes another lipase, SHL, which is in contrast to S. aureus lipases Ca2+ -dependent and has a broad-spectrum lipase and phospholipase activity. The aim of this study was to investigate the role of staphylococcal (phospho) lipases in virulence. For this we constructed a gehA-gehB double deletion mutant in S. aureus USA300 and expressed SHL in agr-positive (accessory gene regulator) and agr-negative S...
November 29, 2017: International Journal of Medical Microbiology: IJMM
Daniel Vázquez-Sánchez, Juliana A Galvão, Marília Oetterer
The major contamination sources, biofilm-forming ability and biocide resistance of Staphylococcus aureus in tilapia-processing plants were evaluated. Twenty-five processing control points were analysed twice in two factories, including whole tilapias, frozen fillets, water and food-contact surfaces. No final product was contaminated with S. aureus. However, high concentrations of S. aureus carrying enterotoxin ( se) genes were found in several processing points of both factories due to the application of inadequate hygienic and handling procedures, which generate a high risk of cross-contamination of the tilapia fillets with staphylococcal enterotoxins...
January 1, 2017: Food Science and Technology International, Ciencia y Tecnología de Los Alimentos Internacional
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