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Staphylococcal biofilm

Yufeng Zhang, Mengjun Cheng, Hao Zhang, Jiaxin Dai, Zhimin Guo, Xinwei Li, Yalu Ji, Ruopeng Cai, Hengyu Xi, Xinwu Wang, Yibing Xue, Changjiang Sun, Xin Feng, Liancheng Lei, Wenyu Han, Jingmin Gu
Treatment of infections caused by staphylococci has become more difficult because of the emergence of multidrug-resistant strains as well as biofilm formation. In this study, we observed the ability of the phage lysin LysGH15 to eliminate staphylococcal planktonic cells and biofilms formed by Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus and Staphylococcus hominis All these strains were sensitive to LysGH15, showing reductions in bacterial counts of approximately 4 log units within 30 min after treatment with 20 μg/mL LysGH15, and the minimum inhibitory concentrations (MICs) ranged from 8 μg/mL to 32 μg/mL...
May 18, 2018: Applied and Environmental Microbiology
I Mesrati, M Saidani, M Jemili, S Ferjeni, A Slim, I Boutiba-Ben Boubaker
Staphylococcus aureus is clinically relevant pathogen that cause device-related infections driven by several virulence factors. In this study we characterize S. aureus isolates involved in medical device-related infections in Tunisian patients. Forty consecutive S. aureus strains causing device-related infections (DRI group) and 47 randomly selected S. aureus strains causing non-device-related infections (NDRI group) were collected. All strains were phenotypically screened for antibiotic susceptibility and biofilm forming ability...
May 15, 2018: International Journal of Antimicrobial Agents
Christine Cho, Aroon T Chande, Lokesh Gakhar, Jason Hunt, Margaret R Ketterer, Michael A Apicella
Nontypeable Haemophilus influenzae (NTHi) has been shown to form biofilms, comprised of extracellular DNA (eDNA), in the middle ear and bronchus during clinical infections. Studies in our laboratory have shown that NTHi possesses a homolog of Staphylococcus aureus thermonuclease (staphylococcal thermonuclease), NTHi nuclease (NTHi Nuc, HI_1296). This enzyme had similar size, heat stability, and divalent cation requirements to those of the staphylococcal homolog as determined by light scattering and circular dichroism spectroscopy...
2018: PloS One
Christen Ravn, Inês Santos Ferreira, Elena Maiolo, Søren Overgaard, Andrej Trampuz
Primary aim of this in vitro study was to test the efficacy of daptomycin to eradicate staphylococcal biofilms on various orthopedic implant materials. Secondary aim was to quantitatively estimate the formation of staphylococcal biofilm. We tested six clinically important biomaterials: cobalt chrome, pure titanium, grid-blasted titanium, porous plasma-coated titanium with/without hydroxyapatite, and polyethylene. Biofilms of S. aureus and S. epidermidis were formed on the samples and thereafter exposed to daptomycin...
May 10, 2018: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
Paola Saporito, Michelle Vang Mouritzen, Anders Løbner-Olesen, Håvard Jenssen
Staphylococcus epidermidis is a common nosocomial pathogen able to form biofilms in indwelling devices, resulting in chronic infections, which are refractory to antibiotics treatment. Staphylococcal biofilms are also associated with the delayed reepithelization and healing of chronic wounds. The human cathelicidin peptide LL-37 has been proven active against S. epidermidis biofilms in vitro and to promote wound healing. As previous studies have demonstrated that fragments of LL-37 could possess an equal antibacterial activity as the parent peptide, we tested whether shorter (12-mer) synthetic fragments of LL-37 maintained the antibiofilm and/or immune modulating activity, aiming at the identification of essential regions within the LL-37 parent sequence...
May 8, 2018: Journal of Peptide Science: An Official Publication of the European Peptide Society
Anders Woetmann, Morten Alhede, Sally Dabelsteen, Thomas Bjarnsholt, Morten Rybtke, Claudia Nastasi, Thorbjørn Krejsgaard, Mads Hald Andersen, Charlotte M Bonefeld, Carsten Geisler, Michael Givskov, Niels Odum
Anti-microbial peptides are produced at outer and inner surfaces by epithelia and innate immune cells in response to bacterial infection. Staphylococcus aureus is an enterotoxin producing, Gram-positive pathogen, which is a major cause of soft tissue infections and life-threatening bacteremia and sepsis. Here we show that (i) skin T cells in chronic wounds infected with S. aureus express interleukin-26 (IL-26) in situ , (ii) staphylococcal enterotoxins (SE) trigger IL-26 expression in T cell lines and primary skin T cells, and (iii) IL-26 triggers death and inhibits biofilm formation and growth of S...
April 13, 2018: Oncotarget
Wafi Siala, Hector Rodriguez-Villalobos, Prabhavathi Fernandes, Paul M Tulkens, Françoise Van Bambeke
Staphylococcal biofilms are a major cause of therapeutic failure, especially when caused by multiresistant strains. Oral fusidic acid is currently being re-developed in the US for skin and skin structure and orthopedic infections, in which biofilms play a major role. The aim of this study was to examine the activity of fusidic acid alone or combined with other anti-staphylococcal drugs against biofilms made by a reference strain and five clinical isolates of Staphylococcus aureus or Staphylococcus epidermidis in in vitro static or dynamic models (microtiter plates and CDC reactor) exposed to clinically-relevant concentrations...
April 30, 2018: Antimicrobial Agents and Chemotherapy
Luís D R Melo, Ana Brandão, Ergun Akturk, Silvio B Santos, Joana Azeredo
Staphylococcus aureus is one of the most relevant opportunistic pathogens involved in many biofilm-associated diseases, and is a major cause of nosocomial infections, mainly due to the increasing prevalence of multidrug-resistant strains. Consequently, alternative methods to eradicate the pathogen are urgent. It has been previously shown that polyvalent staphylococcal kayviruses and their derived endolysins are excellent candidates for therapy. Here we present the characterization of a new bacteriophage: vB_SauM-LM12 (LM12)...
April 7, 2018: Viruses
Katy Vaillancourt, Geneviève LeBel, Li Yi, Daniel Grenier
Greasy pig disease or exudative epidermitis, a generalized or localized skin disease affecting piglets, is mainly caused by Staphylococcus hyicus, although other staphylococcal species such as Staphylococcus aureus may also induce disease. Piglets with skin lesions can be treated systemically with antibiotics. However, antimicrobial resistance to β-lactam antibiotics are now frequently observed in S. hyicus and S. aureus isolates. In this study, the antibacterial activity of plant essential oils as well as their ability to potentiate the effect of several antimicrobial compounds against S...
April 5, 2018: Archives of Microbiology
Ahmed Kotb, Nader S Abutaleb, Mohamed A Seleem, Mohamed Hagras, Haroon Mohammad, Ashraf Bayoumi, Adel Ghiaty, Mohamed N Seleem, Abdelrahman S Mayhoub
A new series of phenylthiazoles with t-butyl lipophilic component was synthesized and their antibacterial activity against a panel of multidrug-resistant bacterial pathogens was evaluated. Five compounds demonstrated promising antibacterial activity against methicillin-resistant staphylococcal strains and several vancomycin-resistant staphylococcal and enterococcal species. Additionally, three derivatives 19, 23 and 26 exhibited rapid bactericidal activity, and remarkable ability to disrupt mature biofilm produced by MRSA USA300...
March 19, 2018: European Journal of Medicinal Chemistry
Eva González-Menéndez, Francisco Noé Arroyo-López, Beatriz Martínez, Pilar García, Antonio Garrido-Fernández, Ana Rodríguez
The use of bacteriophages for killing pathogenic bacteria is a feasible alternative to antibiotics and disinfectants. To obtain the large quantities of phages required for this application, large-scale production of bacteriophages must be optimized. This study aims to define conditions that maximize the phage yield of the virulent and polyvalent staphylococcal bacteriophage vB_SauM-phiIPLA-RODI in broth culture, using the food-grade species Staphylococcus xylosus as the host strain to reduce the risk of growing massive quantities of pathogenic bacteria and therefore, to ensure the safety of the final phage stock...
March 27, 2018: Viruses
G F Dall, S-T J Tsang, P J Gwynne, S P MacKenzie, A H R W Simpson, S J Breusch, M P Gallagher
Objectives: To evaluate putative anti-staphylococcal biofilm antibiotic combinations used in the management of periprosthetic joint infections (PJIs). Methods: Using the dissolvable bead biofilm assay, the minimum biofilm eradication concentration (MBEC) was determined for the most commonly used antimicrobial agents and combination regimens against staphylococcal PJIs. The established fractional inhibitory concentration (FIC) index was modified to create the fractional biofilm eradication concentration (FBEC) index to evaluate synergism or antagonism between antibiotics...
March 14, 2018: Journal of Antimicrobial Chemotherapy
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...
May 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...
May 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...
May 2018: Diagnostic Microbiology and Infectious Disease
Sai Nithya, T R Nimal, Gaurav Baranwal, Maneesha K Suresh, Anju 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...
April 15, 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 (SCC mec ), plays an important role in staphylococci pathogenesis...
October 2017: Malaysian Journal of Medical Sciences: MJMS
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