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Phan MD, Peters KM, Sarkar S, Lukowski SW, Allsopp LP, Moriel DG, Achard MES, Totsika M, Marshall VM, Upton M, Beatson SA, Schembri MA. The serum resistome of a globally disseminated multidrug resistant uropathogenic Escherichia coli clone. PLoS Genet 2013; 9:e1003834. [PMID: 24098145 PMCID: PMC3789825 DOI: 10.1371/journal.pgen.1003834] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 08/12/2013] [Indexed: 01/01/2023] Open
Abstract
Escherichia coli ST131 is a globally disseminated, multidrug resistant clone responsible for a high proportion of urinary tract and bloodstream infections. The rapid emergence and successful spread of E. coli ST131 is strongly associated with antibiotic resistance; however, this phenotype alone is unlikely to explain its dominance amongst multidrug resistant uropathogens circulating worldwide in hospitals and the community. Thus, a greater understanding of the molecular mechanisms that underpin the fitness of E. coli ST131 is required. In this study, we employed hyper-saturated transposon mutagenesis in combination with multiplexed transposon directed insertion-site sequencing to define the essential genes required for in vitro growth and the serum resistome (i.e. genes required for resistance to human serum) of E. coli EC958, a representative of the predominant E. coli ST131 clonal lineage. We identified 315 essential genes in E. coli EC958, 231 (73%) of which were also essential in E. coli K-12. The serum resistome comprised 56 genes, the majority of which encode membrane proteins or factors involved in lipopolysaccharide (LPS) biosynthesis. Targeted mutagenesis confirmed a role in serum resistance for 46 (82%) of these genes. The murein lipoprotein Lpp, along with two lipid A-core biosynthesis enzymes WaaP and WaaG, were most strongly associated with serum resistance. While LPS was the main resistance mechanism defined for E. coli EC958 in serum, the enterobacterial common antigen and colanic acid also impacted on this phenotype. Our analysis also identified a novel function for two genes, hyxA and hyxR, as minor regulators of O-antigen chain length. This study offers novel insight into the genetic make-up of E. coli ST131, and provides a framework for future research on E. coli and other Gram-negative pathogens to define their essential gene repertoire and to dissect the molecular mechanisms that enable them to survive in the bloodstream and cause disease. The emergence and rapid dissemination of new bacterial pathogens presents multiple challenges to healthcare systems, including the need for rapid detection, precise diagnostics, effective transmission control and effective treatment. E. coli ST131 is an example of a recently emerged multidrug resistant pathogen that is capable of causing urinary tract and bloodstream infections with limited available treatment options. In order to increase our molecular understanding of E. coli ST131, we developed a high-throughput transposon mutagenesis system in combination with next generation sequencing to test every gene for its essential role in growth and for its contribution to serum resistance. We identified 315 essential genes, 270 of which were conserved among all currently available complete E. coli genomes. Fifty-six genes that define the serum resistome of E. coli ST131 were identified, including genes encoding membrane proteins, proteins involved in LPS biosynthesis, regulators and several novel proteins with previously unknown function. This study therefore provides an inventory of essential and serum resistance genes that could form a framework for the future development of targeted therapeutics to prevent disease caused by multidrug-resistant E. coli ST131 strains.
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Affiliation(s)
- Minh-Duy Phan
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Kate M. Peters
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Sohinee Sarkar
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Samuel W. Lukowski
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Luke P. Allsopp
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Danilo Gomes Moriel
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Maud E. S. Achard
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Makrina Totsika
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Vikki M. Marshall
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Mathew Upton
- Faculty of Medicine and Dentistry, University of Plymouth, Plymouth, United Kingdom
| | - Scott A. Beatson
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Mark A. Schembri
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- * E-mail:
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Chandramouli KH, Dash S, Zhang Y, Ravasi T, Qian PY. Proteomic and metabolomic profiles of marine Vibrio sp. 010 in response to an antifoulant challenge. BIOFOULING 2013; 29:789-802. [PMID: 23822634 DOI: 10.1080/08927014.2013.805209] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Vibrio spp. have the ability to form biofilms, which may contribute to the subsequent successful colonization by microfouling and macrofouling organisms. The effects of an antifouling compound, poly-ether B, on Vibrio sp. 010 were investigated using flow cytometry, proteomics, and metabolomics. A 2-D gel-based proteomic analysis was used to identify proteins responsive to poly-ether B treatment. The profiles of biofilm metabolites were analyzed by ultra-performance liquid chromatography-mass spectrometry. Poly-ether B caused a significant reduction in viability. The proteins affected by the treatment were related to nucleotide metabolism, the glyoxylate cycle, and stress responses. Metabolites such as tripeptides, fatty acids, and quorum-sensing molecules were regulated differentially. Down-regulation of proteins and metabolites potentially led to a loss in colonisation ability, thereby affecting the structure of the biofilm. These results suggest that the proteins and metabolites identified may serve as target molecules for potent antifouling compounds.
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Affiliation(s)
- Kondethimmanahalli H Chandramouli
- KAUST Global Collaborative Research, Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong SAR, China
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Chima IU, Uchegbu M, Okoli I, Ezema C, Wehke S. Evaluation of the Efficiency of Disinfectants used Against Bacterial Isolates from Intensive Poultry Farming Environments in Imo State, Nigeria. ACTA ACUST UNITED AC 2013. [DOI: 10.3923/jbs.2013.349.356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Larson AM, Klibanov AM. Biocidal Packaging for Pharmaceuticals, Foods, and Other Perishables. Annu Rev Chem Biomol Eng 2013; 4:171-86. [DOI: 10.1146/annurev-chembioeng-061312-103253] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Alexander M. Klibanov
- Departments of 1Chemistry and
- Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139; ,
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Yang HJ, Kim HJ, Yu J, Lee E, Jung YH, Kim HY, Seo JH, Kwon GY, Park JH, Gwack J, Youn SK, Kwon JW, Jun BY, Kim KW, Ahn K, Lee SY, Park JD, Kwon JW, Kim BJ, Lee MS, Do KH, Jang SJ, Pyun BY, Hong SJ. Inhalation toxicity of humidifier disinfectants as a risk factor of children's interstitial lung disease in Korea: a case-control study. PLoS One 2013; 8:e64430. [PMID: 23755124 PMCID: PMC3673956 DOI: 10.1371/journal.pone.0064430] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 04/15/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The occurrence of numerous cases of interstitial lung disease in children (chILD) every spring in Korea starting in 2006 raised suspicion about a causal relationship with the use of humidifier disinfectants (HDs). The aim of this study was to evaluate the association between HD use and the risk of chILD. METHODS This retrospective, 1∶3 matched case-control study consisted of 16 cases of chILD that had developed between 2010 and 2011. The three groups of parallel controls (patients with acute lobar pneumonia, asthma, and healthy children) were matched by age, gender, and index date. Indoor/outdoor environmental risk factors, including HD use, were investigated by asking the guardians to complete a questionnaire. RESULTS The median age of the affected children (43.8% male) was 26 months (18.25-36.25). The chILD group did not differ significantly from the control groups with respect to socio-demographic and clinical variables. Indoor and outdoor environmental factors were not associated with a risk of chILD. However, the previous use of HDs (OR; 2.73. 95% CI; 1.41-5.90, P = 0.00) were independently associated with an increased risk. CONCLUSIONS This study showed that HDs, which are widely used in South Korea in the winter season, independently increased the risk of chILD in spring. Therefore, continuous monitoring and, if needed, changes in policy are essential to prevent and control pediatric diseases caused by toxic chemicals.
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Affiliation(s)
- Hyeon-Jong Yang
- Department of Pediatrics, Pediatric Allergy and Respiratory Center, Soonchunhyang University Hospital, Soonchunhyang University College of Medicine, Seoul, Korea
| | - Hwa-Jung Kim
- Department of Clinical Epidemiology and Biostatistics, Asan Cancer Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Jinho Yu
- Department of Pediatrics, Childhood Asthma Atopy Center, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Eun Lee
- Department of Pediatrics, Childhood Asthma Atopy Center, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
- Research Center for Standardization of Allergic Diseases, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Young-Ho Jung
- Department of Pediatrics, Childhood Asthma Atopy Center, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
- Research Center for Standardization of Allergic Diseases, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Hyung-Young Kim
- Department of Pediatrics, Childhood Asthma Atopy Center, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
- Research Center for Standardization of Allergic Diseases, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
| | - Ju-Hee Seo
- Department of Pediatrics, Korean Cancer Center Hospital, Seoul, Korea
| | - Geun-Yong Kwon
- Division of Epidemic Intelligence Service, Korea Centers for Disease Control and Prevention, Osong, Korea
| | - Ji-Hyuk Park
- Division of Epidemic Intelligence Service, Korea Centers for Disease Control and Prevention, Osong, Korea
| | - Jin Gwack
- Division of Epidemic Intelligence Service, Korea Centers for Disease Control and Prevention, Osong, Korea
| | - Seung-Ki Youn
- Division of Epidemic Intelligence Service, Korea Centers for Disease Control and Prevention, Osong, Korea
| | - Jun-Wook Kwon
- Center for Infectious Disease Surveillance and Response, Korea Centers for Disease Control and Prevention, Osong, Korea
| | - Byung-Yool Jun
- Division of Epidemic Intelligence Service, Korea Centers for Disease Control and Prevention, Osong, Korea
- Center for Infectious Disease Surveillance and Response, Korea Centers for Disease Control and Prevention, Osong, Korea
| | - Kyung Won Kim
- Department of Pediatrics and Institute of Allergy, Biomolecule Secretion Research Center, Yonsei University College of Medicine, Seoul, Korea
| | - Kangmo Ahn
- Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Soo-Young Lee
- Department of Pediatrics, Ajou University Hospital, Ajou University School of Medicine, Suwon, Korea
| | - June-Dong Park
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul University College of Medicine, Seoul, Korea
| | - Ji-Won Kwon
- Department of Pediatrics, Seoul National University Bundang Hospital, Seoul University College of Medicine, Seungnam, Korea
| | - Byoung-Ju Kim
- Department of Pediatrics, Inje University Haeundae Paik Hospital, University of Inje College of Medicine, Busan, Korea
| | - Moo-Song Lee
- Department of Preventive Medicine, Asan Cancer Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Kyung-Hyun Do
- Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Se-Jin Jang
- Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Bok-Yang Pyun
- Department of Pediatrics, Pediatric Allergy and Respiratory Center, Soonchunhyang University Hospital, Soonchunhyang University College of Medicine, Seoul, Korea
- * E-mail: (BYP); (SJH)
| | - Soo-Jong Hong
- Department of Pediatrics, Childhood Asthma Atopy Center, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
- Research Center for Standardization of Allergic Diseases, Asan Medical Center Children’s Hospital, University of Ulsan College of Medicine, Seoul, Korea
- * E-mail: (BYP); (SJH)
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Gnanadhas DP, Marathe SA, Chakravortty D. Biocides--resistance, cross-resistance mechanisms and assessment. Expert Opin Investig Drugs 2012; 22:191-206. [PMID: 23215733 DOI: 10.1517/13543784.2013.748035] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD Antibiotic resistance in bacterial pathogens has increased worldwide leading to treatment failures. Concerns have been raised about the use of biocides as a contributing factor to the risk of antimicrobial resistance (AMR) development. In vitro studies demonstrating increase in resistance have often been cited as evidence for increased risks. It is therefore important to understand the mechanisms of resistance employed by bacteria toward biocides used in consumer products and their potential to impart cross-resistance to therapeutic antibiotics. AREAS COVERED In this review, the mechanisms of resistance and cross-resistance reported in the literature toward biocides commonly used in consumer products are summarized. The physiological and molecular techniques used in describing and examining these mechanisms are reviewed and application of these techniques for systematic assessment of biocides for their potential to develop resistance and/or cross-resistance is discussed. EXPERT OPINION The guidelines in the usage of biocides in household or industrial purpose should be monitored and regulated to avoid the emergence of any MDR strains. The genetic and molecular methods to monitor the resistance development to biocides should be developed and included in preclinical and clinical studies.
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Affiliation(s)
- Divya Prakash Gnanadhas
- Department of Microbiology and Cell Biology, Centre for Infectious Disease Research and Biosafety Laboratories, Indian Institute of Science, Bangalore 560012, India
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Ashraf S, Akhtar N, Ghauri MA, Rajoka MI, Khalid ZM, Hussain I. Polyhexamethylene biguanide functionalized cationic silver nanoparticles for enhanced antimicrobial activity. NANOSCALE RESEARCH LETTERS 2012; 7:267. [PMID: 22625664 PMCID: PMC3492125 DOI: 10.1186/1556-276x-7-267] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 04/23/2012] [Indexed: 05/23/2023]
Abstract
Polyhexamethylene biguanide (PHMB), a broad spectrum disinfectant against many pathogens, was used as a stabilizing ligand for the synthesis of fairly uniform silver nanoparticles. The particles formed were characterized using UV-visible spectroscopy, FTIR, dynamic light scattering, electrophoretic mobility, and TEM to measure their morphology and surface chemistry. PHMB-functionalized silver nanoparticles were then evaluated for their antimicrobial activity against a gram-negative bacterial strain, Escherichia coli. These silver nanoparticles were found to have about 100 times higher bacteriostatic and bactericidal activities, compared to the previous reports, due to the combined antibacterial effect of silver nanoparticles and PHMB. In addition to other applications, PHMB-functionalized silver nanoparticles would be extremely useful in textile industry due to the strong interaction of PHMB with cellulose fabrics.
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Affiliation(s)
- Sumaira Ashraf
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, Faisalabad, 38000, Pakistan
- Department of Chemistry, School of Science & Engineering (SSE), Lahore University of Management Sciences (LUMS), DHA, Lahore Cantt, 54792, Pakistan
| | - Nasrin Akhtar
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, Faisalabad, 38000, Pakistan
| | - Muhammad Afzal Ghauri
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, Faisalabad, 38000, Pakistan
| | - Muhammad Ibrahim Rajoka
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, Faisalabad, 38000, Pakistan
- Department of Bioinformatics and Biotechnology, Government College University, Allama Iqbal Road, Faisalabad, 38000, Pakistan
| | - Zafar M Khalid
- National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road, Faisalabad, 38000, Pakistan
| | - Irshad Hussain
- Department of Chemistry, School of Science & Engineering (SSE), Lahore University of Management Sciences (LUMS), DHA, Lahore Cantt, 54792, Pakistan
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Condell O, Sheridan Á, Power KA, Bonilla-Santiago R, Sergeant K, Renaut J, Burgess C, Fanning S, Nally JE. Comparative proteomic analysis of Salmonella tolerance to the biocide active agent triclosan. J Proteomics 2012; 75:4505-19. [PMID: 22579747 DOI: 10.1016/j.jprot.2012.04.044] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 04/26/2012] [Accepted: 04/28/2012] [Indexed: 01/01/2023]
Abstract
Concern has been expressed about the overuse of biocides in farm animal production and food industries. Biocide application can create selective pressures that lead to increased tolerance to one or more of these compounds and are concomitant with the emergence of cross-resistance to antibiotics. A triclosan sensitive Salmonella enterica serovar Typhimurium and the isogenic triclosan tolerant mutant were studied at the proteomic level in order to elucidate cellular mechanisms that facilitate biocide tolerance. 2-D differential fluorescent gel electrophoresis (DIGE) compared protein profiles of parent and mutant Salmonella, in the presence and absence of triclosan. Differentially expressed proteins were identified by mass spectrometry and divided into two groups: Group A describes proteins differentially expressed between susceptible and triclosan tolerant Salmonella and includes the known triclosan target FabI which contained a mutation at the triclosan target binding site. Group B identified proteins differentially expressed in response to triclosan exposure and defines a general cell defence network. Only four proteins were common to both groups highlighting the diverse range of pathways employed by Salmonella to counteract biocides. These data suggest that sub-lethal concentrations of triclosan induce discernible changes in the proteome of exposed Salmonella and provide insights into mechanisms of response and tolerance.
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Affiliation(s)
- O Condell
- UCD Centre for Food Safety & the Centre for Food-borne Zoonomics, School of Public Health, Physiotherapy & Population Science, Ireland
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Woods J, Boegli L, Kirker KR, Agostinho AM, Durch AM, Delancey Pulcini E, Stewart PS, James GA. Development and application of a polymicrobial, in vitro, wound biofilm model. J Appl Microbiol 2012; 112:998-1006. [PMID: 22353049 DOI: 10.1111/j.1365-2672.2012.05264.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
AIMS The goal of this investigation was to develop an in vitro, polymicrobial, wound biofilm capable of supporting the growth of bacteria with variable oxygen requirements. METHODS AND RESULTS The strict anaerobe Clostridium perfringens was isolated by cultivating wound homogenates using the drip-flow reactor (DFR), and a three-species biofilm model was established using methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Cl. perfringens in the colony-drip-flow reactor model. Plate counts revealed that MRSA, Ps. aeruginosa and Cl. perfringens grew to 7·39 ± 0·45, 10·22 ± 0·22 and 7·13 ± 0·77 log CFU per membrane, respectively. The three-species model was employed to evaluate the efficacy of two antimicrobial dressings, Curity™ AMD and Acticoat™, compared to sterile gauze controls. Microbial growth on Curity™ AMD and gauze was not significantly different, for any species, whereas Acticoat™ was found to significantly reduce growth for all three species. CONCLUSIONS Using the colony-DFR, a three-species biofilm was successfully grown, and the biofilms displayed a unique structure consisting of distinct layers that appeared to be inhabited exclusively or predominantly by a single species. SIGNIFICANCE AND IMPACT OF THE STUDY The primary accomplishment of this study was the isolation and growth of an obligate anaerobe in an in vitro model without establishing an artificially anaerobic environment.
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Affiliation(s)
- J Woods
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
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Hadaway L. Polyhexamethylene Biguanide Dressing – Another Promising Tool to Reduce Catheter-related Bloodstream Infection. ACTA ACUST UNITED AC 2011. [DOI: 10.2309/java.15-4-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
Purpose
This article provides a description of polyhexamethylene biguanide (PHMB), its current uses and clinical outcomes, and potential uses.
Review of Relevant Literature
PHMB is an antiseptic agent from the cationic biocide family, which also includes chlorhexidine. In vitro testing has found it to be effective against gram-positive and gram-negative bacteria including methicillin-resistant staphylococcus aureus, fungi and viruses. Its action is directed toward disruption of the cell wall, a mechanism not known for developing resistance. PHMB is currently used for many other products and industries for more than 50 years. Dressings impregnated with PHMB are now successfully being used to prevent surgical site infections.
Discussion
Elimination of catheter-related bloodstream infection (CR-BSI) is now the achievable goal for all healthcare settings. The use of PHMB provides another engineering tool targeting the skin as the source of these infections. Successful use with prevention of surgical site infections is now being reported. These wounds can become infected with the same organisms as those found in CRBSI.
Implications for Clinical Practice
This agent should be considered for clinical studies to determine the rates of CRBSI reduction resulting from its use.
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Jiang B, Larson JC, Drapala PW, Pérez-Luna VH, Kang-Mieler JJ, Brey EM. Investigation of lysine acrylate containing poly(N-isopropylacrylamide) hydrogels as wound dressings in normal and infected wounds. J Biomed Mater Res B Appl Biomater 2011; 100:668-76. [DOI: 10.1002/jbm.b.31991] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 09/13/2011] [Accepted: 09/20/2011] [Indexed: 01/02/2023]
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Elsztein C, de Lucena RM, de Morais MA. The resistance of the yeast Saccharomyces cerevisiae to the biocide polyhexamethylene biguanide: involvement of cell wall integrity pathway and emerging role for YAP1. BMC Mol Biol 2011; 12:38. [PMID: 21854579 PMCID: PMC3175164 DOI: 10.1186/1471-2199-12-38] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Accepted: 08/19/2011] [Indexed: 11/19/2022] Open
Abstract
Background Polyhexamethylene biguanide (PHMB) is an antiseptic polymer that is mainly used for cleaning hospitals and pools and combating Acantamoeba infection. Its fungicide activity was recently shown by its lethal effect on yeasts that contaminate the industrial ethanol process, and on the PE-2 strain of Saccharomyces cerevisiae, one of the main fermenting yeasts in Brazil. This pointed to the need to know the molecular mechanism that lay behind the cell resistance to this compound. In this study, we examined the factors involved in PHMB-cell interaction and the mechanisms that respond to the damage caused by this interaction. To achieve this, two research strategies were employed: the expression of some genes by RT-qPCR and the analysis of mutant strains. Results Cell Wall integrity (CWI) genes were induced in the PHMB-resistant Saccharomyces cerevisiae strain JP-1, although they are poorly expressed in the PHMB-sensitive Saccharomyces cerevisiae PE2 strain. This suggested that PHMB damages the glucan structure on the yeast cell wall. It was also confirmed by the observed sensitivity of the yeast deletion strains, Δslg1, Δrom2, Δmkk2, Δslt2, Δknr4, Δswi4 and Δswi4, which showed that the protein kinase C (PKC) regulatory mechanism is involved in the response and resistance to PHMB. The sensitivity of the Δhog1 mutant was also observed. Furthermore, the cytotoxicity assay and gene expression analysis showed that the part played by YAP1 and CTT1 genes in cell resistance to PHMB is unrelated to oxidative stress response. Thus, we suggested that Yap1p can play a role in cell wall maintenance by controlling the expression of the CWI genes. Conclusion The PHMB treatment of the yeast cells activates the PKC1/Slt2 (CWI) pathway. In addition, it is suggested that HOG1 and YAP1 can play a role in the regulation of CWI genes.
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Affiliation(s)
- Carolina Elsztein
- Interdepartmental Research Group in Metabolic Engineering, Av, Moraes Rego, 1235, Cidade Universitária, 50670-901, Recife, PE, Brazil
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Lima TB, Silva ON, Migliolo L, Souza-Filho CR, Gonçalves EG, Vasconcelos IM, Oliveira JTA, Amaral AC, Franco OL. A Kunitz proteinase inhibitor from corms of Xanthosoma blandum with bactericidal activity. JOURNAL OF NATURAL PRODUCTS 2011; 74:969-975. [PMID: 21520894 DOI: 10.1021/np200312r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Bacterial infections directly affect the world's population, and this situation has been aggravated by indiscriminate use of antimicrobial agents, which can generate resistant microorganisms. In this report, an initial screening of proteins with antibacterial activity from corms of 15 species of the Xanthosoma genus was conducted. Since Xanthosoma blandum corms showed enhanced activity toward bacteria, a novel protein with bactericidal activity was isolated from this particular species. Edman degradation was used for protein N-termini determination; the primary structure showed similarities with Kunitz inhibitors, and this protein was named Xb-KTI. This protein was further challenged against serine proteinases from different sources, showing clear inhibitory activities. Otherwise, no hemolytic activity was observed for Xb-KTI. The results demonstrate the biotechnological potential of Xb-KTI, the first proteinase inhibitor with antimicrobial activity described in the Xanthosoma genus.
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Affiliation(s)
- Thaís B Lima
- Centro de Análises Proteômicas e Bioquímicas, Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, Brasília, Brazil
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Importance of porins for biocide efficacy against Mycobacterium smegmatis. Appl Environ Microbiol 2011; 77:3068-73. [PMID: 21398489 DOI: 10.1128/aem.02492-10] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycobacteria are among the microorganisms least susceptible to biocides but cause devastating diseases, such as tuberculosis, and increasingly opportunistic infections. The exceptional resistance of mycobacteria to toxic solutes is due to an unusual outer membrane, which acts as an efficient permeability barrier, in synergy with other resistance mechanisms. Porins are channel-forming proteins in the outer membrane of mycobacteria. In this study we used the alamarBlue assay to show that the deletion of Msp porins in isogenic mutants increased the resistance of Mycobacterium smegmatis to isothiazolinones (methylchloroisothiazolinone [MCI]/methylisothiazolinone [MI] and octylisothiazolinone [2-n-octyl-4-isothiazolin-3-one; OIT]), formaldehyde-releasing biocides {hexahydrotriazine [1,3,5-tris (2-hydroxyethyl)-hexahydrotriazine; HHT] and methylenbisoxazolidine [N,N'-methylene-bis-5-(methyloxazolidine); MBO]}, and the lipophilic biocides polyhexamethylene biguanide and octenidine dihydrochloride 2- to 16-fold. Furthermore, the susceptibility of the porin triple mutant against a complex disinfectant was decreased 8-fold compared to wild-type (wt) M. smegmatis. Efficacy testing in the quantitative suspension test EN 14348 revealed 100-fold improved survival of the porin mutant in the presence of this biocide. These findings underline the importance of porins for the susceptibility of M. smegmatis to biocides.
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65
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Stratton TR, Applegate BM, Youngblood JP. Effect of Steric Hindrance on the Properties of Antibacterial and Biocompatible Copolymers. Biomacromolecules 2010; 12:50-6. [PMID: 21158441 DOI: 10.1021/bm1009624] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thomas R. Stratton
- School of Materials Engineering, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907, United States, and Departments of Food Science and Biological Sciences, Purdue University, 745 Agriculture Mall Drive, West Lafayette, Indiana 47907, United States
| | - Bruce M. Applegate
- School of Materials Engineering, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907, United States, and Departments of Food Science and Biological Sciences, Purdue University, 745 Agriculture Mall Drive, West Lafayette, Indiana 47907, United States
| | - Jeffrey P. Youngblood
- School of Materials Engineering, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907, United States, and Departments of Food Science and Biological Sciences, Purdue University, 745 Agriculture Mall Drive, West Lafayette, Indiana 47907, United States
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66
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Scimeca CL, Bharara M, Fisher TK, Kimbriel H, Mills JL, Armstrong DG. An update on pharmacological interventions for diabetic foot ulcers. Foot Ankle Spec 2010; 3:285-302. [PMID: 20685955 DOI: 10.1177/1938640010376994] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Diabetic foot ulcers are the most common lower extremity complications of diabetes. Peripheral neuropathy and peripheral vascular disease are the underlying risk factors for diabetic foot ulcers, subsequently leading to infections and requiring antimicrobial therapy for the management of the disease. Each risk factor is a target for clinical intervention, with the intent to delay or prevent disease progression to amputation. The effective therapy includes interdisciplinary care, which involves optimized pharmacological interventions in concert with other treatments such as debridement strategies and specialized wound dressings. The pharmacological therapy alone cannot lead to successful therapy, and therefore, these supplementary techniques/modalities should not be overlooked. It is therefore the aim of this report to review various pharmacological interventions, specific to the diabetic foot and wound healing, along with incorporation of advanced therapies required to achieve a multifaceted treatment of diabetic foot ulcers and provide basis for superior drugs as well as drug delivery systems.
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Affiliation(s)
- Christy L Scimeca
- Southern Arizona Limb Salvage Alliance, Department of Surgery, University of Arizona College of Medicine, Tucson, Arizona, USA
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67
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Global transcriptome analysis of the Escherichia coli O157 response to Houttuynia Cordata Thunb. BIOCHIP JOURNAL 2010. [DOI: 10.1007/s13206-010-4312-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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68
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Bromberg L, Chang EP, Alvarez-Lorenzo C, Magariños B, Concheiro A, Hatton TA. Binding of functionalized paramagnetic nanoparticles to bacterial lipopolysaccharides and DNA. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:8829-8835. [PMID: 20155986 DOI: 10.1021/la904589p] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Magnetite and metallic cobalt-based nanoparticles with sizes ranging from 10 to 300 nm and surface-functionalized with poly(hexamethylene biguanide) (PHMBG) are introduced as capable lipopolysaccharide (LPS)-sequestering agents. The nanoparticles efficiently bind to whole E. coli cells and can be used to separate the cells effectively from suspension using a magnet. A fluorescence dye displacement assay shows strong affinities of the nanoparticles for lipid A, the glycolipid component of LPS responsible for septic shock. The particle-lipid A affinity is of the same order of magnitude or higher than that of polymyxin B. The affinity of smaller (< 50 nm) magnetite particles modified with PHMBG to lipid A is several-fold higher than that of their larger counterparts (> 100 nm) due to their higher surface area to volume ratio. The nanoparticles possess high saturation capacity for double-stranded lambdaDNA from E. coli, with which particle-polyelectrolyte complexes are formed. The PHMBG-modified nanoparticles are potent bactericides, inhibiting E. coli viability and growth at concentrations at < or = 10 microg/mL.
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Affiliation(s)
- Lev Bromberg
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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69
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Pinto F, Maillard JY, Denyer SP. Effect of surfactants, temperature, and sonication on the virucidal activity of polyhexamethylene biguanide against the bacteriophage MS2. Am J Infect Control 2010; 38:393-8. [PMID: 20006410 DOI: 10.1016/j.ajic.2009.08.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Revised: 08/14/2009] [Accepted: 08/19/2009] [Indexed: 11/25/2022]
Abstract
BACKGROUND Virucidal compounds are essential in preventing the transmission of viral infection in the health care environment. Understanding their mechanisms of action is necessary to improve their efficacy. Inactivation of viruses is less documented than that of bacteria notably because different types of virus have diverse response to microbicides, making difficult to establish an inactivation pattern. METHODS The effect of viral aggregates on the virucidal activity of polyhexamethylene biguanide-based microbicide VANTOCIL TG (Arch Chemicals, Manchester, UK) against the bacteriophage MS2 was investigated by using in combination a standard suspension efficacy test under different conditions and dynamic light scattering measuring the presence and size of aggregates. RESULTS Temperature had a key role in increasing significantly the virucidal activity of VANTOCIL TG, reducing virus concentration by 4-log(10) within 10 minutes at 40 degrees C. The high temperature was linked to a reduction of viral aggregates despite the exposure to the biguanide. In addition, the viral inactivation kinetic became significantly more linear at 30 degrees C and 40 degrees C. Such results were also observed with sonication during treatment, where a first-order kinetic was observed. However, the addition of surfactants, even though there was evidence of a decrease in viral clumps, did not enhance the virucidal activity of polyhexamethylene biguanide. CONCLUSION The presence of viral aggregates was an important factor in the virucidal efficacy of the biguanide as demonstrated by the correlation among high temperature, decrease in aggregates, and increase in activity, although it is possible that high temperatures might also cause conformational changes of the viral capsid, increasing the sensitivity of virions to the microbicide.
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71
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Han X, Dorsey-Oresto A, Malik M, Wang JY, Drlica K, Zhao X, Lu T. Escherichia coli genes that reduce the lethal effects of stress. BMC Microbiol 2010; 10:35. [PMID: 20128927 PMCID: PMC2824699 DOI: 10.1186/1471-2180-10-35] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Accepted: 02/04/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The continuing emergence of antimicrobial resistance requires the development of new compounds and/or enhancers of existing compounds. Genes that protect against the lethal effects of antibiotic stress are potential targets of enhancers. To distinguish such genes from those involved in drug uptake and efflux, a new susceptibility screen is required. RESULTS Transposon (Tn5)-mediated mutagenesis was used to create a library of Escherichia coli mutants that was screened for hypersensitivity to the lethal action of quinolones and counter-screened to have wild-type bacteriostatic susceptibility. Mutants with this novel "hyperlethal" phenotype were found. The phenotype was transferable to other E. coli strains by P1-mediated transduction, and for a subset of the mutants the phenotype was complemented by the corresponding wild-type gene cloned into a plasmid. Thus, the inactivation of these genes was responsible for hyperlethality. Nucleotide sequence analysis identified 14 genes, mostly of unknown function, as potential factors protecting from lethal effects of stress. The 14 mutants were killed more readily than wild-type cells by mitomycin C and hydrogen peroxide; nine were also more readily killed by UV irradiation, and several exhibited increased susceptibility to killing by sodium dodecyl sulfate. No mutant was more readily killed by high temperature. CONCLUSIONS A new screening strategy identified a diverse set of E. coli genes involved in the response to lethal antimicrobial and environmental stress, with some genes being involved in the response to multiple stressors. The gene set, which differed from sets previously identified with bacteriostatic assays, provides an entry point for obtaining small-molecule enhancers that will affect multiple antimicrobial agents.
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Affiliation(s)
- Xiulin Han
- Yunnan Institute of Microbiology, Yunnan University, 52 Cui Hu Bei Lu, Kunming, Yunnan 650091, PR China
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Jackson AP, Thomas GH, Parkhill J, Thomson NR. Evolutionary diversification of an ancient gene family (rhs) through C-terminal displacement. BMC Genomics 2009; 10:584. [PMID: 19968874 PMCID: PMC2935791 DOI: 10.1186/1471-2164-10-584] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Accepted: 12/07/2009] [Indexed: 12/29/2022] Open
Abstract
Background Rhs genes are prominent features of bacterial genomes that have previously been implicated in genomic rearrangements in E. coli. By comparing rhs repertoires across the Enterobacteriaceae, this study provides a robust explanation of rhs diversification and evolution, and a mechanistic model of how rhs diversity is gained and lost. Results Rhs genes are ubiquitous and comprise six structurally distinct lineages within the Enterobacteriaceae. There is considerable intergenomic variation in rhs repertoire; for instance, in Salmonella enterica, rhs are restricted to mobile elements, while in Escherichia coli one rhs lineage has diversified through transposition as older lineages have been deleted. Overall, comparative genomics reveals frequent, independent gene gains and losses, as well as occasional lateral gene transfer, in different genera. Furthermore, we demonstrate that Rhs 'core' domains and variable C-termini are evolutionarily decoupled, and propose that rhs diversity is driven by homologous recombination with circular intermediates. Existing C-termini are displaced by laterally acquired alternatives, creating long arrays of dissociated 'tips' that characterize the appearance of rhs loci. Conclusion Rhs repertoires are highly dynamic among Enterobacterial genomes, due to repeated gene gains and losses. In contrast, the primary structures of Rhs genes are evolutionarily conserved, indicating that rhs sequence diversity is driven, not by rapid mutation, but by the relatively slow evolution of novel core/tip combinations. Hence, we predict that a large pool of dissociated rhs C-terminal tips exists episomally and these are potentially transmitted across taxonomic boundaries.
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Affiliation(s)
- Andrew P Jackson
- The Wellcome Trust Sanger Institute, Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.
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73
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Nde CW, Jang HJ, Toghrol F, Bentley WE. Global transcriptomic response of Pseudomonas aeruginosa to chlorhexidine diacetate. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:8406-8415. [PMID: 19924977 DOI: 10.1021/es9015475] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Pseudomonas aeruginosa is implicated in nosocomial infections and chronic respiratory infections in cystic fibrosis patients. Chlorhexidine diacetate (CHX) is a biguanide disinfectant used for bacterial control in the hospital and agricultural and domestic environments. A better understanding of the mechanism of action of CHX and the resulting response elicited by P. aeruginosa to CHX will facilitate its effective utilization for P. aeruginosa control in these environments. This study presents, for the first time, the transcriptomic response of P. aeruginosa to 0.008 mM CHX after 10 and 60 min. Our results reveal that, after both treatment times, membrane transport, oxidative phosphorylation, and electron transport genes were downregulated. After 10 min, DNA repair was downregulated and the oprH gene that blocks the self-promoted uptake of antimicrobials was upregulated. After 60 min, outer membrane protein, flagellum, pilus, oxidative phosphorylation, and electron transport genes were downregulated. The mexC and mexD genes of the MexCD-OprJ multidrug efflux pump were significantly upregulated after both treatment times. The results of this study improve our understanding of the mode of action of CHX on P. aeruginosa and provide insights into the mechanism of action of other biguanide disinfectants which can be used for the development of more efficient disinfectants.
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Affiliation(s)
- Chantal W Nde
- Center for Biosystems Research, University of Maryland Biotechnology Institute, College Park, Maryland 20742, USA.
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74
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Adelmann R, Mennicken M, Popescu D, Heine E, Keul H, Moeller M. Functional polymethacrylates as bacteriostatic polymers. Eur Polym J 2009. [DOI: 10.1016/j.eurpolymj.2009.08.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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75
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Pinto F, Maillard JY, Denyer SP, McGeechan P. Polyhexamethylene biguanide exposure leads to viral aggregation. J Appl Microbiol 2009; 108:1880-8. [PMID: 19895651 DOI: 10.1111/j.1365-2672.2009.04596.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS This study reports the activity of two biguanides against MS2 bacteriophage used as a surrogate virus for nonenveloped mammalian viruses and provides an explanation as to their apparent limited efficacy. METHODS AND RESULTS When tested in a standard suspension test, two polyhexamethylene biguanides (PHMB), VANTOCIL TG and COSMOCIL CQ, reduced the viability of MS2 by only 1-2 log(10) PFU ml(-1). Exposure time up to 30 min did not affect the activity of the biguanides, although both PHMB were shown to strongly interact with MS2 proteins. CONCLUSIONS Inactivation kinetics and change in virus hydrophobicity suggested that PHMB induces the formation of viral aggregates. This hypothesis was supported using dynamic light scattering that showed an increase in viral aggregates sizes (up to 500 nm) in a concentration-dependent manner. SIGNIFICANCE AND IMPACT OF THE STUDY It has been reported that viral aggregation is responsible for virus survival to the biocide exposure. Here, this might be the case, because the virucidal activity of the biguanides was modest and viral aggregation important. The formation of viral aggregates during virus exposure to PHMB was unlikely to overestimate the virucidal potential of the biguanides.
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Affiliation(s)
- F Pinto
- Welsh School of Pharmacy, Cardiff University, Cardiff, UK
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76
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rhs genes are potential markers for multilocus sequence typing of Escherichia coli O157:H7 strains. Appl Environ Microbiol 2009; 75:5853-62. [PMID: 19633111 DOI: 10.1128/aem.00859-09] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
DNA sequence-based molecular subtyping methods such as multilocus sequence typing (MLST) are commonly used to generate phylogenetic inferences for monomorphic pathogens. The development of an effective MLST scheme for subtyping Escherichia coli O157:H7 has been hindered in the past due to the lack of sequence variation found within analyzed housekeeping and virulence genes. A recent study suggested that rhs genes are under strong positive selection pressure, and therefore in this study we analyzed these genes within a diverse collection of E. coli O157:H7 strains for sequence variability. Eighteen O157:H7 strains from lineages I and II and 15 O157:H7 strains from eight clades were included. Examination of these rhs genes revealed 44 polymorphic loci (PL) and 10 sequence types (STs) among the 18 lineage strains and 280 PL and 12 STs among the 15 clade strains. Phylogenetic analysis using rhs genes generally grouped strains according to their known lineage and clade classifications. These findings also suggested that O157:H7 strains from clades 6 and 8 fall into lineage I/II and that strains of clades 1, 2, 3, and 4 fall into lineage I. Additionally, unique markers were found in rhsA and rhsJ that might be used to define clade 8 and clade 6. Therefore, rhs genes may be useful markers for phylogenetic analysis of E. coli O157:H7.
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77
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Bromberg L, Raduyk S, Hatton TA. Functional Magnetic Nanoparticles for Biodefense and Biological Threat Monitoring and Surveillance. Anal Chem 2009; 81:5637-45. [DOI: 10.1021/ac9003437] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Lev Bromberg
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, and Department of Biological Sciences, Southern Methodist University, Dallas, Texas 75275-0376
| | - Svetlana Raduyk
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, and Department of Biological Sciences, Southern Methodist University, Dallas, Texas 75275-0376
| | - T. Alan Hatton
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, and Department of Biological Sciences, Southern Methodist University, Dallas, Texas 75275-0376
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Oulé MK, Azinwi R, Bernier AM, Kablan T, Maupertuis AM, Mauler S, Nevry RK, Dembélé K, Forbes L, Diop L. Polyhexamethylene guanidine hydrochloride-based disinfectant: a novel tool to fight meticillin-resistant Staphylococcus aureus and nosocomial infections. J Med Microbiol 2009; 57:1523-1528. [PMID: 19018024 DOI: 10.1099/jmm.0.2008/003350-0] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Polyhexamethylene guanidine hydrochloride (PHMGH), an antimicrobial biocide of the guanidine family, was tested for efficacy against quality-control strains of Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella choleraesuis, meticillin-resistant S. aureus (MRSA) and Escherichia coli. Bactericidal activity against S. aureus, P. aeruginosa and Salmonella choleraesuis was determined using the official methods of analysis of the Association of Official Analytical Chemists, with modifications as recommended by the Canadian General Standards Board. For MRSA and E. coli, the MIC and minimal bactericidal concentration were determined using the broth dilution technique. The experiments were carried out at 20 degrees C under a range of conditions including varying PHMGH concentration (0.001-0.1 %), contact time (0.5-10 min) and water type (distilled, tap and hard water). The phenol coefficient values determined with S. aureus, Salmonella choleraesuis and P. aeruginosa were 7.5, 6.1 and 5, respectively. No matter what type of water was used to make the dilutions, PHMGH killed MRSA and E. coli at concentrations as low as 0.04 and 0.005 % (w/v), respectively, within 1.5 min. The mode of action of PHMGH was elucidated by transmission electron microscopy: the cell envelope was broken, resulting in cell content leakage into the medium. The ultimate aim of this study was to show that PHMGH can be used as an odourless, colourless, non-corrosive and harmless disinfectant for hospital and household facilities.
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Affiliation(s)
- Mathias K Oulé
- Department of Biological Science, Faculty of Science, Collège Universitaire de Saint-Boniface, 200 Avenue de la Cathédrale, Winnipeg, Manitoba R2H 0H7, Canada
| | - Richard Azinwi
- Department of Biological Science, Faculty of Science, Collège Universitaire de Saint-Boniface, 200 Avenue de la Cathédrale, Winnipeg, Manitoba R2H 0H7, Canada
| | - Anne-Marie Bernier
- Department of Biological Science, Faculty of Science, Collège Universitaire de Saint-Boniface, 200 Avenue de la Cathédrale, Winnipeg, Manitoba R2H 0H7, Canada
| | - Tano Kablan
- Unité de Formation et de Recherche en Sciences et Technologie des Aliments, Abobo Adjamé University, 02 BP 801, Abidjan 02, Cote d'Ivoire
| | - Anne-Marie Maupertuis
- Department of Biological Science, Faculty of Science, Collège Universitaire de Saint-Boniface, 200 Avenue de la Cathédrale, Winnipeg, Manitoba R2H 0H7, Canada
| | - Stephanie Mauler
- Department of Biological Science, Faculty of Science, Collège Universitaire de Saint-Boniface, 200 Avenue de la Cathédrale, Winnipeg, Manitoba R2H 0H7, Canada
| | - Rose K Nevry
- Unité de Formation et de Recherche en Sciences et Technologie des Aliments, Abobo Adjamé University, 02 BP 801, Abidjan 02, Cote d'Ivoire
| | - Korami Dembélé
- Department of Biological Science, Faculty of Science, Collège Universitaire de Saint-Boniface, 200 Avenue de la Cathédrale, Winnipeg, Manitoba R2H 0H7, Canada
| | - Lorraine Forbes
- Department of Biological Science, Faculty of Science, Collège Universitaire de Saint-Boniface, 200 Avenue de la Cathédrale, Winnipeg, Manitoba R2H 0H7, Canada
| | - Lamine Diop
- Department of Biological Science, Faculty of Science, Collège Universitaire de Saint-Boniface, 200 Avenue de la Cathédrale, Winnipeg, Manitoba R2H 0H7, Canada
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Abstract
The lysogenic bacteriophage APSE infects "Candidatus Hamiltonella defensa," a facultative endosymbiont of aphids and other sap-feeding insects. This endosymbiont has established a beneficial association with aphids, increasing survivorship following attack by parasitoid wasps. Although APSE and "Ca. Hamiltonella defensa" are effectively maternally transmitted between aphid generations, they can also be horizontally transferred among insect hosts, which results in genetically distinct "Ca. Hamiltonella defensa" strains infecting the same aphid species and sporadic distributions of both APSE and "Ca. Hamiltonella defensa" among hosts. Aphids infected only with "Ca. Hamiltonella defensa" have significantly less protection than those infected with both "Ca. Hamiltonella defensa" and APSE. This protection has been proposed to be connected to eukaryote-targeted toxins previously discovered in the genomes of two characterized APSE strains. In this study, we have sequenced partial genomes from seven additional APSE strains to address the evolution and extent of toxin variation in this phage. The APSE lysis region has been a hot spot for nonhomologous recombination of novel virulence cassettes. We identified four new toxins from three protein families, Shiga-like toxin, cytolethal distending toxin, and YD-repeat toxins. These recombination events have also resulted in reassortment of the downstream lysozyme and holin genes. Analysis of the conserved APSE genes flanking the variable toxin cassettes reveals a close phylogenetic association with phage sequences from two other facultative endosymbionts of insects. Thus, phage may act as a conduit for ongoing gene exchange among heritable endosymbionts.
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80
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In vitro study of the effect of cationic biocides on bacterial population dynamics and susceptibility. Appl Environ Microbiol 2008; 74:4825-34. [PMID: 18515475 DOI: 10.1128/aem.00573-08] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cationic biocides (CBs) are widely used in domestic and public hygiene and to control biofouling and microbial contamination in industry. The increased use of biocides has led to concern regarding possible reductions in biocide effectiveness. Domestic drain microcosms were stabilized for 5 months and then exposed to polyhexamethylene biguanide (PHMB) at 0.1, 0.2, and 0.4g liter(-1) over 6 months and characterized throughout by differential culture, together with eubacterial-specific PCR-denaturing gradient gel electrophoresis. Additionally, MICs and minimal bactericidal concentrations (MBCs) for bacteria previously isolated from a domestic drain (n = 18) and the human skin (n = 13) were determined before, during, and after escalating, sublethal exposure (14 passages) to two quaternary ammonium compounds (QAC1 and QAC2), the bisbiguanide chlorhexidine (CHX), and PHMB. Exposure of the drain microcosm to PHMB did not decrease the total viable count although significant (P < 0.01) decreases in recovery were observed for the gram-positive cocci with associated clonal expansion of pseudomonads (from ca. 0.1% of the population to ca. 10%). This clonal expansion was also manifested as elevations in bacteria that could grow in the presence of PHMB, CHX, and QAC1. Decreases in susceptibility (greater than twofold) occurred for 10/31 of the test bacteria for QAC1, 14/31 for QAC2, 10/31 for CHX, and 7/31 for PHMB. Exposure of microcosms to PHMB targeted gram-positive species and caused the clonal expansion of pseudomonads. In terms of prolonged-sublethal passage on CBs, exposure to all the biocides tested resulted in susceptibility decreases for a proportion of test bacteria, but refractory clones were not generated.
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81
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Polyhexamethyl biguanide can eliminate contaminant yeasts from fuel-ethanol fermentation process. J Ind Microbiol Biotechnol 2008; 35:967-73. [PMID: 18506496 DOI: 10.1007/s10295-008-0371-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2008] [Accepted: 05/12/2008] [Indexed: 10/22/2022]
Abstract
Industrial ethanol fermentation is a non-sterile process and contaminant microorganisms can lead to a decrease in industrial productivity and significant economic loss. Nowadays, some distilleries in Northeastern Brazil deal with bacterial contamination by decreasing must pH and adding bactericides. Alternatively, contamination can be challenged by adding a pure batch of Saccharomyces cerevisiae-a time-consuming and costly process. A better strategy might involve the development of a fungicide that kills contaminant yeasts while preserving S. cerevisiae cells. Here, we show that polyhexamethyl biguanide (PHMB) inhibits and kills the most important contaminant yeasts detected in the distilleries of Northeastern Brazil without affecting the cell viability and fermentation capacity of S. cerevisiae. Moreover, some physiological data suggest that PHMB acts through interaction with the yeast membrane. These results support the development of a new strategy for controlling contaminant yeast population whilst keeping industrial yields high.
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82
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Whole genome microarray analysis of the expression profile of Escherichia coli in response to exposure to para-nitrophenol. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s1872-2423(08)00006-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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83
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Maillard JY. Bacterial resistance to biocides in the healthcare environment: should it be of genuine concern? J Hosp Infect 2007; 65 Suppl 2:60-72. [PMID: 17540245 DOI: 10.1016/s0195-6701(07)60018-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The emergence of bacterial resistance following exposure in healthcare facilities has been a recurrent topic of interest over the last 10 years. The overwhelming and increasing body of evidence from studies in vitro showed that bacteria have an immense capacity to respond to chemical stress brought upon by biocides. Empirically two major types of mechanisms have been described: intrinsic and acquired. However, the increasing documented response from bacteria exposed to biocide in conditions close to those found in practice suggests that intrinsic resistance does not adequately describe bacterial survival mechanisms, and that other terms such as biofilm resistance and environmental resistance would be therefore more appropriate. In addition, such terms are more relevant when describing in-situ conditions. The lack of evidence of bacterial resistance in practice and the inability to correlate emerging bacterial resistance from in-vitro experiments with practical situations is a major drawback when attempting to ascertain whether emerging bacterial resistance in healthcare facilities is of genuine concern. Microbial resistance to high or in-use concentration of biocides has been described in practice, although it remains uncommon. The efficacy of biocides in eliminating bacterial contaminants within healthcare facilities has to be questioned with the widespread and increasing use of products containing low concentrations of biocide or possessing low bactericidal activity, as is the selection of less susceptible bacteria following such exposure.
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Affiliation(s)
- J-Y Maillard
- Welsh School of Pharmacy, Cardiff University, Cardiff, UK.
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Mattinen L, Nissinen R, Riipi T, Kalkkinen N, Pirhonen M. Host-extract induced changes in the secretome of the plant pathogenic bacterium
Pectobacterium atrosepticum. Proteomics 2007; 7:3527-37. [PMID: 17726675 DOI: 10.1002/pmic.200600759] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Pectobacterium atrosepticum is a Gram-negative plant pathogenic bacterium that causes rotting in potato stems and tubers. The secreted proteins of this pathogen were analyzed with proteomics from culture supernatant of cells grown in minimal medium supplemented with host extracts. More than 40 proteins were identified, among them known virulence determinants, such as pectic enzymes, metalloprotease, and virulence protein Svx, along with flagella proteins, GroEL and cyclophilin-type chaperones and several hypothetical proteins or proteins with unknown function. Some of the identified proteins may be involved in utilization of nutrients or transport of minerals. Northern and real-time RT-PCR analyses suggested that most of the proteins upregulated by plant extract were transcriptionally regulated. Among the identified proteins were VgrG and four homologs of hemolysin-coregulated proteins (Hcps). A mutant strain lacking one of the hcp genes was not affected in virulence, while a bacterial strain overexpressing the same gene was shown to have increased virulence, which suggests that these proteins may be new virulence determinants of P. atrosepticum. Comparison of the secretomes of wild type cells and hrcC mutant defective in Type III secretion suggested that the production of the identified proteins was independent of functional Type III secretion system.
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Affiliation(s)
- Laura Mattinen
- Department of Applied Biology, University of Helsinki, Finland
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