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Pan Y, Li G, Liu R, Guo J, Liu Y, Liu M, Zhang X, Chi L, Xu K, Wu R, Zhang Y, Li Y, Gao X, Li S. Unnatural activities and mechanistic insights of cytochrome P450 PikC gained from site-specific mutagenesis by non-canonical amino acids. Nat Commun 2023; 14:1669. [PMID: 36966128 PMCID: PMC10039885 DOI: 10.1038/s41467-023-37288-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 03/09/2023] [Indexed: 03/27/2023] Open
Abstract
Cytochrome P450 enzymes play important roles in the biosynthesis of macrolide antibiotics by mediating a vast variety of regio- and stereoselective oxidative modifications, thus improving their chemical diversity, biological activities, and pharmaceutical properties. Tremendous efforts have been made on engineering the reactivity and selectivity of these useful biocatalysts. However, the 20 proteinogenic amino acids cannot always satisfy the requirement of site-directed/random mutagenesis and rational protein design of P450 enzymes. To address this issue, herein, we practice the semi-rational non-canonical amino acid mutagenesis for the pikromycin biosynthetic P450 enzyme PikC, which recognizes its native macrolide substrates with a 12- or 14-membered ring macrolactone linked to a deoxyamino sugar through a unique sugar-anchoring mechanism. Based on a semi-rationally designed substrate binding strategy, non-canonical amino acid mutagenesis at the His238 position enables the unnatural activities of several PikC mutants towards the macrolactone precursors without any sugar appendix. With the aglycone hydroxylating activities, the pikromycin biosynthetic pathway is rewired by the representative mutant PikCH238pAcF carrying a p-acetylphenylalanine residue at the His238 position and a promiscuous glycosyltransferase. Moreover, structural analysis of substrate-free and three different enzyme-substrate complexes of PikCH238pAcF provides significant mechanistic insights into the substrate binding and catalytic selectivity of this paradigm biosynthetic P450 enzyme.
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Affiliation(s)
- Yunjun Pan
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Guobang Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Ruxin Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Jiawei Guo
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Yunjie Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Mingyu Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Xingwang Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266237, China
| | - Luping Chi
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Kangwei Xu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, China
| | - Ruibo Wu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, China
| | - Yuzhong Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266237, China
| | - Yuezhong Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China
| | - Xiang Gao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China.
| | - Shengying Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, 266237, China.
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266237, China.
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2
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Godijk NG, Bootsma MCJ, van Werkhoven HC, Schweitzer VA, de Greeff SC, Schoffelen AF, Bonten MJM. Does plasmid-based beta-lactam resistance increase E. coli infections: Modelling addition and replacement mechanisms. PLoS Comput Biol 2022; 18:e1009875. [PMID: 35286302 PMCID: PMC8947615 DOI: 10.1371/journal.pcbi.1009875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 03/24/2022] [Accepted: 01/27/2022] [Indexed: 11/19/2022] Open
Abstract
Infections caused by antibiotic-resistant bacteria have become more prevalent during past decades. Yet, it is unknown whether such infections occur in addition to infections with antibiotic-susceptible bacteria, thereby increasing the incidence of infections, or whether they replace such infections, leaving the total incidence unaffected. Observational longitudinal studies cannot separate both mechanisms. Using plasmid-based beta-lactam resistant E. coli as example we applied mathematical modelling to investigate whether seven biological mechanisms would lead to replacement or addition of infections. We use a mathematical neutral null model of individuals colonized with susceptible and/or resistant E. coli, with two mechanisms implying a fitness cost, i.e., increased clearance and decreased growth of resistant strains, and five mechanisms benefitting resistance, i.e., 1) increased virulence, 2) increased transmission, 3) decreased clearance of resistant strains, 4) increased rate of horizontal plasmid transfer, and 5) increased clearance of susceptible E. coli due to antibiotics. Each mechanism is modelled separately to estimate addition to or replacement of antibiotic-susceptible infections. Fitness costs cause resistant strains to die out if other strain characteristics are maintained equal. Under the assumptions tested, increased virulence is the only mechanism that increases the total number of infections. Other benefits of resistance lead to replacement of susceptible infections without changing the total number of infections. As there is no biological evidence that plasmid-based beta-lactam resistance increases virulence, these findings suggest that the burden of disease is determined by attributable effects of resistance rather than by an increase in the number of infections.
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Affiliation(s)
- Noortje G. Godijk
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
- * E-mail:
| | - Martin C. J. Bootsma
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
- Department of Mathematics, Faculty of Sciences, Utrecht University, Utrecht, the Netherlands
| | - Henri C. van Werkhoven
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Valentijn A. Schweitzer
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Sabine C. de Greeff
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Annelot F. Schoffelen
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Marc J. M. Bonten
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
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3
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Eisenberg P, Albert L, Teuffel J, Zitzow E, Michaelis C, Jarick J, Sehlke C, Große L, Bader N, Nunes-Alves A, Kreikemeyer B, Schindelin H, Wade RC, Fiedler T. The Non-phosphorylating Glyceraldehyde-3-Phosphate Dehydrogenase GapN Is a Potential New Drug Target in Streptococcus pyogenes. Front Microbiol 2022; 13:802427. [PMID: 35242116 PMCID: PMC8886048 DOI: 10.3389/fmicb.2022.802427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 01/14/2022] [Indexed: 01/01/2023] Open
Abstract
The strict human pathogen Streptococcus pyogenes causes infections of varying severity, ranging from self-limiting suppurative infections to life-threatening diseases like necrotizing fasciitis or streptococcal toxic shock syndrome. Here, we show that the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase GapN is an essential enzyme for S. pyogenes. GapN converts glyceraldehyde 3-phosphate into 3-phosphoglycerate coupled to the reduction of NADP to NADPH. The knock-down of gapN by antisense peptide nucleic acids (asPNA) significantly reduces viable bacterial counts of S. pyogenes laboratory and macrolide-resistant clinical strains in vitro. As S. pyogenes lacks the oxidative part of the pentose phosphate pathway, GapN appears to be the major NADPH source for the bacterium. Accordingly, other streptococci that carry a complete pentose phosphate pathway are not prone to asPNA-based gapN knock-down. Determination of the crystal structure of the S. pyogenes GapN apo-enzyme revealed an unusual cis-peptide in proximity to the catalytic binding site. Furthermore, using a structural modeling approach, we correctly predicted competitive inhibition of S. pyogenes GapN by erythrose 4-phosphate, indicating that our structural model can be used for in silico screening of specific GapN inhibitors. In conclusion, the data provided here reveal that GapN is a potential target for antimicrobial substances that selectively kill S. pyogenes and other streptococci that lack the oxidative part of the pentose phosphate pathway.
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Affiliation(s)
- Philip Eisenberg
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre, Rostock, Germany
| | - Leon Albert
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Jonathan Teuffel
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany
| | - Eric Zitzow
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre, Rostock, Germany
| | - Claudia Michaelis
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre, Rostock, Germany
| | - Jane Jarick
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre, Rostock, Germany
| | - Clemens Sehlke
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre, Rostock, Germany
| | - Lisa Große
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre, Rostock, Germany
| | - Nicole Bader
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Ariane Nunes-Alves
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany.,Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Bernd Kreikemeyer
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre, Rostock, Germany
| | - Hermann Schindelin
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Rebecca C Wade
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies, Heidelberg, Germany.,Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany.,Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany
| | - Tomas Fiedler
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre, Rostock, Germany
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Donders G, Greenhouse P, Donders F, Engel U, Paavonen J, Mendling W. Genital Tract GAS Infection ISIDOG Guidelines. J Clin Med 2021; 10:jcm10092043. [PMID: 34068785 PMCID: PMC8126195 DOI: 10.3390/jcm10092043] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 04/18/2021] [Accepted: 04/23/2021] [Indexed: 02/07/2023] Open
Abstract
There has been an increasing worldwide incidence of invasive group A streptococcal (GAS) disease in pregnancy and in the puerperal period over the past 30 years. Postpartum Group A streptococci infection, and in particular streptococcal toxic shock syndrome (TSS) and necrotizing fasciitis, can be life threatening and difficult to treat. Despite antibiotics and supportive therapy, and in some cases advanced extensive surgery, mortality associated with invasive group A streptococcal postpartum endometritis, necrotizing fasciitis, and toxic shock syndrome remains high, up to 40% of postpartum septic deaths. It now accounts for more than 75,000 deaths worldwide every year. Postpartum women have a 20-fold increased incidence of GAS disease compared to non-pregnant women. Despite the high incidence, many invasive GAS infections are not diagnosed in a timely manner, resulting in potentially preventable maternal and neonatal deaths. In this paper the specific characteristics of GAS infection in the field of Ob/Gyn are brought to our attention, resulting in guidelines to improve our awareness, early recognition and timely treatment of the disease. New European prevalence data of vaginal GAS colonization are presented, alongside two original case histories. Additionally, aerobic vaginitis is proposed as a supplementary risk factor for invasive GAS diseases.
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Affiliation(s)
- Gilbert Donders
- Femicare, Clinical Research for Women, 3300 Tienen, Belgium;
- Department of Obstetrics and Gynecology, University Hospital Antwerp, 2000 Antwerp, Belgium
- Regional Hospital H Hart, 3300 Tienen, Belgium
- Correspondence: ; Tel.: +32-38-214413
| | | | | | - Ulrike Engel
- Department of Ob/Gyn Maternité, Centre Hospitalier, 1210 Luxembourg, Luxembourg;
| | - Jorma Paavonen
- Department of Obstetrics and Gynecology, Helsinki University Hospital, 00260 Helsinki, Finland;
| | - Werner Mendling
- German Centre for Infections in Gynaecology and Obstetrics, St. Anna Hospital, 42109 Wuppertal, Germany;
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5
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Assessing the Role of Pharyngeal Cell Surface Glycans in Group A Streptococcus Biofilm Formation. Antibiotics (Basel) 2020; 9:antibiotics9110775. [PMID: 33158121 PMCID: PMC7694240 DOI: 10.3390/antibiotics9110775] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 10/27/2020] [Accepted: 10/27/2020] [Indexed: 01/06/2023] Open
Abstract
Group A Streptococcus (GAS) causes 700 million infections and accounts for half a million deaths per year. Antibiotic treatment failure rates of 20–40% have been observed. The role host cell glycans play in GAS biofilm formation in the context of GAS pharyngitis and subsequent antibiotic treatment failure has not been previously investigated. GAS serotype M12 GAS biofilms were assessed for biofilm formation on Detroit 562 pharyngeal cell monolayers following enzymatic removal of all N-linked glycans from pharyngeal cells with PNGase F. Removal of N-linked glycans resulted in an increase in biofilm biomass compared to untreated controls. Further investigation into the removal of terminal mannose and sialic acid residues with α1-6 mannosidase and the broad specificity sialidase (Sialidase A) also found that biofilm biomass increased significantly when compared to untreated controls. Increases in biofilm biomass were associated with increased production of extracellular polymeric substances (EPS). Furthermore, it was found that M12 GAS biofilms grown on untreated pharyngeal monolayers exhibited a 2500-fold increase in penicillin tolerance compared to planktonic GAS. Pre-treatment of monolayers with exoglycosidases resulted in a further doubling of penicillin tolerance in resultant biofilms. Lastly, an additional eight GAS emm-types were assessed for biofilm formation in response to terminal mannose and sialic acid residue removal. As seen for M12, biofilm biomass on monolayers increased following removal of terminal mannose and sialic acid residues. Collectively, these data demonstrate that pharyngeal cell surface glycan structures directly impact GAS biofilm formation in a strain and glycan specific fashion.
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6
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Vyas HKN, Proctor EJ, McArthur J, Gorman J, Sanderson-Smith M. Current Understanding of Group A Streptococcal Biofilms. Curr Drug Targets 2020; 20:982-993. [PMID: 30947646 PMCID: PMC6700754 DOI: 10.2174/1389450120666190405095712] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 04/01/2019] [Accepted: 04/02/2019] [Indexed: 02/01/2023]
Abstract
Background: It has been proposed that GAS may form biofilms. Biofilms are microbial communities that aggregate on a surface, and exist within a self-produced matrix of extracellular polymeric substances. Biofilms offer bacteria an increased survival advantage, in which bacteria persist, and resist host immunity and antimicrobial treatment. The biofilm phenotype has long been recognized as a virulence mechanism for many Gram-positive and Gram-negative bacteria, however very little is known about the role of biofilms in GAS pathogenesis. Objective: This review provides an overview of the current knowledge of biofilms in GAS pathogenesis. This review assesses the evidence of GAS biofilm formation, the role of GAS virulence factors in GAS biofilm formation, modelling GAS biofilms, and discusses the polymicrobial nature of biofilms in the oropharynx in relation to GAS. Conclusion: Further study is needed to improve the current understanding of GAS as both a mono-species biofilm, and as a member of a polymicrobial biofilm. Improved modelling of GAS biofilm formation in settings closely mimicking in vivo conditions will ensure that biofilms generated in the lab closely reflect those occurring during clinical infection.
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Affiliation(s)
- Heema K N Vyas
- School of Chemistry and Molecular Bioscience, and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
| | - Emma-Jayne Proctor
- School of Chemistry and Molecular Bioscience, and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
| | - Jason McArthur
- School of Chemistry and Molecular Bioscience, and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
| | - Jody Gorman
- School of Chemistry and Molecular Bioscience, and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
| | - Martina Sanderson-Smith
- School of Chemistry and Molecular Bioscience, and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
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7
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Wang B, Cleary PP. Intracellular Invasion by Streptococcus pyogenes: Invasins, Host Receptors, and Relevance to Human Disease. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0049-2018. [PMID: 31267891 PMCID: PMC10957197 DOI: 10.1128/microbiolspec.gpp3-0049-2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Indexed: 12/23/2022] Open
Abstract
The human oral-nasal mucosa is the primary reservoir for Streptococcus pyogenes infections. Although the most common infection of consequence in temperate climates is pharyngitis, the past 25 years have witnessed a dramatic increase in invasive disease in many regions of the world. Historically, S. pyogenes has been associated with sepsis and fulminate systemic infections, but the mechanism by which these streptococci traverse mucosal or epidermal barriers is not understood. The discovery that S. pyogenes can be internalized by mammalian epithelial cells at high frequencies (1-3) and/or open tight junctions to pass between cells (4) provides potential explanations for changes in epidemiology and the ability of this species to breach such barriers. In this article, the invasins and pathways that S. pyogenes uses to reach the intracellular state are reviewed, and the relationship between intracellular invasion and human disease is discussed.
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Affiliation(s)
- Beinan Wang
- Institute of Microbiology, Chinese Academy of Sciences, Beijing China
| | - P Patrick Cleary
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN
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8
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Di Bonaventura G, Pompilio A, Monaco M, Pimentel de Araujo F, Baldassarri L, Pantosti A, Gherardi G. Adhesion and biofilm formation by Staphylococcus aureus clinical isolates under conditions relevant to the host: relationship with macrolide resistance and clonal lineages. J Med Microbiol 2018; 68:148-160. [PMID: 30540247 DOI: 10.1099/jmm.0.000893] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
PURPOSE Staphylococcus aureus isolates, collected from various clinical samples, were analysed to evaluate the contribution of the genetic background of both erythromycin-resistant (ERSA) and -susceptible (ESSA) S. aureus strains to biofilm formation. METHODS A total of 66 ESSA and 43 ERSA clinical isolates were studied for adhesiveness and biofilm formation under different atmospheres. All isolates were evaluated for phenotypic and genotypic macrolide resistance, and for clonal relatedness by pulsed-field gel electrophoresis (PFGE), and by spa typing on representative isolates. RESULTS A high genetic heterogeneity was encountered, although 10 major PFGE types accounted for 86 % with a few small spatially and temporally related clusters. Overall, biofilm formation under anoxia was significantly lower than under oxic and micro-aerophilic atmospheres. Biofilm formation by ESSA was significantly higher compared to ERSA under oxic and micro-aerophilic conditions. Adhesiveness to plastic was significantly higher among respiratory tract infection isolates under micro-aerophilic conditions, while surgical site infection isolates formed significantly higher biomass of biofilm under oxic and micro-aerophilic atmospheres compared to anoxia. Pulsotype 2 and 4 strains formed significantly higher biofilm biomass than pulsotype 1, with strains belonging to CC8 forming significantly more compared to those belonging to CC5, under both oxic and micro-aerophilic atmospheres. CONCLUSIONS S. aureus biofilm formation appears to be more efficient in ESSA than ERSA, associated with specific S. aureus lineages, mainly CC8 and CC15, and affected by atmosphere. Further studies investigating the relationship between antibiotic resistance and biofilm formation could prove useful in the development of new strategies for the management of S. aureus infections.
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Affiliation(s)
- Giovanni Di Bonaventura
- 1Department of Medical, Oral and Biotechnological Sciences, 'G. d'Annunzio' University of Chieti-Pescara, Via dei Vestini 31, 66100 Chieti (CH), Italy
| | - Arianna Pompilio
- 1Department of Medical, Oral and Biotechnological Sciences, 'G. d'Annunzio' University of Chieti-Pescara, Via dei Vestini 31, 66100 Chieti (CH), Italy
| | - Monica Monaco
- 2Department of Infectious, Parasitic and Immune-mediated Diseases, Italian National Health Institute, Viale Regina Elena 299, 00161 Rome, Italy
| | - Fernanda Pimentel de Araujo
- 2Department of Infectious, Parasitic and Immune-mediated Diseases, Italian National Health Institute, Viale Regina Elena 299, 00161 Rome, Italy
| | - Lucilla Baldassarri
- 3Centro Nazionale Sostanze Chimiche, Cosmetici e Protezione del Consumatore, Italian National Health Institute, Viale Regina Elena 299, 00161 Rome, Italy
| | - Annalisa Pantosti
- 2Department of Infectious, Parasitic and Immune-mediated Diseases, Italian National Health Institute, Viale Regina Elena 299, 00161 Rome, Italy
| | - Giovanni Gherardi
- 4Department of Medicine, Campus Biomedico University, Via Alvaro del Portillo 200, 00128 Rome, Italy
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Marini E, Magi G, Mingoia M, Pugnaloni A, Facinelli B. Antimicrobial and Anti-Virulence Activity of Capsaicin Against Erythromycin-Resistant, Cell-Invasive Group A Streptococci. Front Microbiol 2015; 6:1281. [PMID: 26617603 PMCID: PMC4643145 DOI: 10.3389/fmicb.2015.01281] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 10/31/2015] [Indexed: 12/02/2022] Open
Abstract
Capsaicin (8-methyl-N-vanillyl-6-nonenamide) is the active component of Capsicum plants (chili peppers), which are grown as food and for medicinal purposes since ancient times, and is responsible for the pungency of their fruit. Besides its multiple pharmacological and physiological properties (pain relief, cancer prevention, and beneficial cardiovascular, and gastrointestinal effects) capsaicin has recently attracted considerable attention because of its antimicrobial and anti-virulence activity. This is the first study of its in vitro antibacterial and anti-virulence activity against Streptococcus pyogenes (Group A streptococci, GAS), a major human pathogen. The test strains were previously characterized, erythromycin-susceptible (n = 5) and erythromycin-resistant (n = 27), cell-invasive pharyngeal isolates. The MICs of capsaicin were 64–128 μg/mL (the most common MIC was 128 μg/mL). The action of capsaicin was bactericidal, as suggested by MBC values that were equal or close to the MICs, and by early detection of dead cells in the live/dead assay. No capsaicin-resistant mutants were obtained in single-step resistance selection studies. Interestingly, growth in presence of sublethal capsaicin concentrations induced an increase in biofilm production (p ≤ 0.05) and in the number of bacteria adhering to A549 monolayers, and a reduction in cell-invasiveness and haemolytic activity (both p ≤ 0.05). Cell invasiveness fell so dramatically that a highly invasive strain became non-invasive. The dose-response relationship, characterized by opposite effects of low and high capsaicin doses, suggests a hormetic response. The present study documents that capsaicin has promising bactericidal activity against erythromycin-resistant, cell-invasive pharyngeal GAS isolates. The fact that sublethal concentrations inhibited cell invasion and reduced haemolytic activity, two important virulence traits of GAS, is also interesting, considering that cell-invasive, erythromycinresistant strains can evade β-lactams by virtue of intracellular location and macrolides by virtue of resistance, thus escaping antibiotic treatment. By inhibiting intracellular invasion and haemolytic activity, capsaicin could thus prevent both formation of a difficult to eradicate intracellular reservoir, and infection spread to deep tissues.
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Affiliation(s)
- Emanuela Marini
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche , Ancona, Italy
| | - Gloria Magi
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche , Ancona, Italy
| | - Marina Mingoia
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche , Ancona, Italy
| | - Armanda Pugnaloni
- Department of Clinical and Molecular Sciences, Polytechnic University of Marche , Ancona, Italy
| | - Bruna Facinelli
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche , Ancona, Italy
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10
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Marini E, Palmieri C, Magi G, Facinelli B. Recombination between Streptococcus suis ICESsu32457 and Streptococcus agalactiae ICESa2603 yields a hybrid ICE transferable to Streptococcus pyogenes. Vet Microbiol 2015; 178:99-104. [DOI: 10.1016/j.vetmic.2015.04.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 04/13/2015] [Accepted: 04/17/2015] [Indexed: 10/23/2022]
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11
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Gherardi G, Petrelli D, Di Luca MC, Pimentel de Araujo F, Bernaschi P, Repetto A, Bellesi J, Vitali LA. Decline in macrolide resistance rates among Streptococcus pyogenes causing pharyngitis in children isolated in Italy. Eur J Clin Microbiol Infect Dis 2015; 34:1797-802. [PMID: 26024763 PMCID: PMC4545180 DOI: 10.1007/s10096-015-2414-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 05/13/2015] [Indexed: 11/21/2022]
Abstract
Macrolides are often used to treat group A streptococcus (GAS) infections, but their resistance rates reached high proportions worldwide. The aim of the present study was to give an update on the characteristics and contemporary prevalence of macrolide-resistant pharyngeal GAS in Central Italy. A total of 592 isolates causing pharyngitis in children were collected in the period 2012–2013. Clonality was assessed by emm typing and pulsed-field gel electrophoresis (PFGE) for all macrolide-resistant strains and for selected susceptible isolates. Genetic determinants of resistance were screened by polymerase chain reaction (PCR). Forty-four GAS were erythromycin-resistant (7.4 %). Among them, 52.3 % and 50 % were clindamycin- and tetracycline-resistant, respectively. erm(B)-positive isolates (52.3 %) expressed the constitutive cMLSB phenotype. mef(A) and its associated M phenotype were recorded in 40.9 % of the cases. The remaining erm(A)-positive isolates expressed the iMLSB phenotype. Seventeen tetracycline-resistant isolates carried tet(M) and five isolates carried tet(O). Twenty-five emm types were found among all strains, with the predominance of emm types 12, 89, 1, and 4. Eleven emm types and 12 PFGE clusters characterized macrolide-resistant strains, with almost two-thirds belonging to emm12, emm4, and emm11. Macrolide-susceptible and -resistant emm types 12, 89, 11, and 4 shared related PFGE profiles. There was a dramatic decline in macrolide resistance in Central Italy among pharyngeal GAS isolates in 2012–2013 when compared to previous studies from the same region (p < 0.05), although macrolide consumption remained stable over the past 15 years. We observed a decrease in the proportion of macrolide-resistant strains within emm types commonly associated with macrolide resistance in the past, namely emm12, 1, and 89.
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Affiliation(s)
- G Gherardi
- University Campus Bio-Medico, 00128, Roma, Italy
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Magi G, Marini E, Facinelli B. Antimicrobial activity of essential oils and carvacrol, and synergy of carvacrol and erythromycin, against clinical, erythromycin-resistant Group A Streptococci. Front Microbiol 2015; 6:165. [PMID: 25784902 PMCID: PMC4347498 DOI: 10.3389/fmicb.2015.00165] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 02/12/2015] [Indexed: 01/27/2023] Open
Abstract
In the present study, we have evaluated the in vitro antibacterial activity of essential oils from Origanum vulgare, Thymus vulgaris, Lavandula angustifolia, Mentha piperita, and Melaleuca alternifolia against 32 erythromycin-resistant [Mininum Inhibitory Concentration (MIC) ≥1 μg/mL; inducible, constitutive, and efflux-mediated resistance phenotype; erm(TR), erm(B), and mef(A) genes] and cell-invasive Group A streptococci (GAS) isolated from children with pharyngotonsillitis in Italy. Over the past decades erythromycin resistance in GAS has emerged in several countries; strains combining erythromycin resistance and cell invasiveness may escape β-lactams because of intracellular location and macrolides because of resistance, resulting in difficulty of eradication and recurrent pharyngitis. Thyme and origanum essential oils demonstrated the highest antimicrobial activity with MICs ranging from 256 to 512 μg/mL. The phenolic monoterpene carvacrol [2-Methyl-5-(1-methylethyl) phenol] is a major component of the essential oils of Origanum and Thymus plants. MICs of carvacrol ranged from 64 to 256 μg/mL. In the live/dead assay several dead cells were detected as early as 1 h after incubation with carvacrol at the MIC. In single-step resistance selection studies no resistant mutants were obtained. A synergistic action of carvacrol and erythromycin was detected by the checkerboard assay and calculation of the Fractional Inhibitory Concentration (FIC) Index. A 2- to 2048-fold reduction of the erythromycin MIC was documented in checkerboard assays. Synergy (FIC Index ≤0.5) was found in 21/32 strains and was highly significant (p < 0.01) in strains where resistance is expressed only in presence of erythromycin. Synergy was confirmed in 17/23 strains using 24-h time-kill curves in presence of carvacrol and erythromycin. Our findings demonstrated that carvacrol acts either alone or in combination with erythromycin against erythromycin-resistant GAS and could potentially serve as a novel therapeutic tool.
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Affiliation(s)
- Gloria Magi
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona Italy
| | - Emanuela Marini
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona Italy
| | - Bruna Facinelli
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona Italy
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Fiedler T, Köller T, Kreikemeyer B. Streptococcus pyogenes biofilms-formation, biology, and clinical relevance. Front Cell Infect Microbiol 2015; 5:15. [PMID: 25717441 PMCID: PMC4324238 DOI: 10.3389/fcimb.2015.00015] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 01/26/2015] [Indexed: 12/31/2022] Open
Abstract
Streptococcus pyogenes (group A streptococci, GAS) is an exclusive human bacterial pathogen. The virulence potential of this species is tremendous. Interactions with humans range from asymptomatic carriage over mild and superficial infections of skin and mucosal membranes up to systemic purulent toxic-invasive disease manifestations. Particularly the latter are a severe threat for predisposed patients and lead to significant death tolls worldwide. This places GAS among the most important Gram-positive bacterial pathogens. Many recent reviews have highlighted the GAS repertoire of virulence factors, regulators and regulatory circuits/networks that enable GAS to colonize the host and to deal with all levels of the host immune defense. This covers in vitro and in vivo studies, including animal infection studies based on mice and more relevant, macaque monkeys. It is now appreciated that GAS, like many other bacterial species, do not necessarily exclusively live in a planktonic lifestyle. GAS is capable of microcolony and biofilm formation on host cells and tissues. We are now beginning to understand that this feature significantly contributes to GAS pathogenesis. In this review we will discuss the current knowledge on GAS biofilm formation, the biofilm-phenotype associated virulence factors, regulatory aspects of biofilm formation, the clinical relevance, and finally contemporary treatment regimens and future treatment options.
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Affiliation(s)
- Tomas Fiedler
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre Rostock, Germany
| | - Thomas Köller
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre Rostock, Germany
| | - Bernd Kreikemeyer
- Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Medical Centre Rostock, Germany
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14
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Gherardi G, Imperi M, Palmieri C, Magi G, Facinelli B, Baldassarri L, Pataracchia M, Creti R. Genetic diversity and virulence properties of Streptococcus dysgalactiae subsp. equisimilis from different sources. J Med Microbiol 2014; 63:90-98. [DOI: 10.1099/jmm.0.062109-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A recent increase in virulence of pathogenic Streptococcus dysgalactiae subsp. equisimilis (SDSE) has been widely proposed. Such an increase may be partly explained by the acquisition of new virulence traits by horizontal gene transfer from related streptococci such as Streptococcus pyogenes (GAS) and Streptococcus agalactiae (GBS). A collection of 54 SDSE strains isolated in Italy in the years 2000–2010 from different sources (paediatric throat carriage, invasive and non-invasive diseases) was characterized by emm typing and pulsed-field gel electrophoresis (PFGE) analysis. The virulence repertoire was evaluated by PCR for the presence of GAS superantigen (spe) genes, the streptolysin S (sagA) gene, the group G fibronectin-binding protein (gfbA) gene and GAS–GBS alpha-like protein family (alp) genes; moreover, the ability to invade human epithelial cells was investigated. Resistance to tetracycline, erythromycin and clindamycin was assessed. The combined use of emm typing and PFGE proved to be a reliable strategy for the epidemiological analysis of SDSE isolates. The most frequent emm types were the same as those more frequently reported in other studies, thus indicating the diffusion of a limited number of a few successful emm types fit to disseminate in humans. The speG gene was detected in SDSE strains of different genetic backgrounds. Erythromycin resistance determined by the erm(T) gene, and the unusual, foggy MLSB phenotype, observed in one and seven strains, respectively, have never previously, to our knowledge, been reported in SDSE. Moreover, a new member of the alp family was identified. The identification of new antibiotic and virulence determinants, despite the small size of the sample analysed, shows the importance of constant attention to monitoring the extent of lateral gene transfer in this emerging pathogen.
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Affiliation(s)
- Giovanni Gherardi
- Dipartimento di Centro Integrato di Ricerca (CIR), Università Campus Bio-Medico, Rome, Italy
| | - Monica Imperi
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Claudio Palmieri
- Dipartimento di Scienze Biomediche e Sanità Pubblica, Sezione Microbiologia, Università Politecnica delle Marche, Ancona, Italy
| | - Gloria Magi
- Dipartimento di Scienze Biomediche e Sanità Pubblica, Sezione Microbiologia, Università Politecnica delle Marche, Ancona, Italy
| | - Bruna Facinelli
- Dipartimento di Scienze Biomediche e Sanità Pubblica, Sezione Microbiologia, Università Politecnica delle Marche, Ancona, Italy
| | - Lucilla Baldassarri
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Marco Pataracchia
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Roberta Creti
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Rome, Italy
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Catalanotti P, Catania MR, Lucido M, Martini S, Gallè F, Ortega De Luna L, Rossano F. T Serotyping and Genomic Profile of Erythromycin- Resistant or -SensitiveStreptococcus pyogenesIsolated in Campania Region, Italy. J Chemother 2013; 17:131-7. [PMID: 15920897 DOI: 10.1179/joc.2005.17.2.131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Streptococcus pyogenes causes mild infections, such as pharyngitis, and severe infections, such as necrotizing fascitis. In recent years, erythromycin-resistant strains of S. pyogenes have been reported in many countries. In some areas of Italy, increased rates of erythromycin resistance were first observed in the mid-1990s. Here, we report epidemiological T serotyping, invasiveness, erythromycin resistance, and PFGE patterns of 99 S. pyogenes strains isolated at the Laboratory of Clinical Microbiology of the Second University of Naples, Italy. Regarding T serotyping, 26 of 99 strains were W+, 16 strains were U+, 16 were X+, and 14 were agglutinated by anti T serum. A low percentage revealed Y+. Twelve strains were not T serotyped. PFGE patterns showed species polymorphism; however, inside the various serotypes, we demonstrated a fair homogeneity. No correlation among invasiveness and T serotype or PFGE pattern has been shown. Twenty-two of 99 strains were erythromycin-resistant.
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Affiliation(s)
- P Catalanotti
- Dipartimento di Medicina Sperimentale, Sezione di Microbiologia e Microbiologia Clinica, Seconda Università di Napoli, Naples, Italy.
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16
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Protective mechanisms of respiratory tract Streptococci against Streptococcus pyogenes biofilm formation and epithelial cell infection. Appl Environ Microbiol 2012; 79:1265-76. [PMID: 23241973 DOI: 10.1128/aem.03350-12] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Streptococcus pyogenes (group A streptococci [GAS]) encounter many streptococcal species of the physiological microbial biome when entering the upper respiratory tract of humans, leading to the question how GAS interact with these bacteria in order to establish themselves at this anatomic site and initiate infection. Here we show that S. oralis and S. salivarius in direct contact assays inhibit growth of GAS in a strain-specific manner and that S. salivarius, most likely via bacteriocin secretion, also exerts this effect in transwell experiments. Utilizing scanning electron microscopy documentation, we identified the tested strains as potent biofilm producers except for GAS M49. In mixed-species biofilms, S. salivarius dominated the GAS strains, while S. oralis acted as initial colonizer, building the bottom layer in mixed biofilms and thereby allowing even GAS M49 to form substantial biofilms on top. With the exception of S. oralis, artificial saliva reduced single-species biofilms and allowed GAS to dominate in mixed biofilms, although the overall two-layer structure was unchanged. When covered by S. oralis and S. salivarius biofilms, epithelial cells were protected from GAS adherence, internalization, and cytotoxic effects. Apparently, these species can have probiotic effects. The use of Affymetrix array technology to assess HEp-2 cell transcription levels revealed modest changes after exposure to S. oralis and S. salivarius biofilms which could explain some of the protective effects against GAS attack. In summary, our study revealed a protection effect of respiratory tract bacteria against an important airway pathogen and allowed a first in vitro insight into local environmental processes after GAS enter the respiratory tract.
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McFadden J, Fry L, Powles A, Kimber I. Concepts in psoriasis: psoriasis and the extracellular matrix. Br J Dermatol 2012; 167:980-6. [DOI: 10.1111/j.1365-2133.2012.11149.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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18
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Savic DJ, McShan WM. Long-term survival of Streptococcus pyogenes in rich media is pH-dependent. MICROBIOLOGY-SGM 2012; 158:1428-1436. [PMID: 22361943 DOI: 10.1099/mic.0.054478-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The mechanisms that allow Streptococcus pyogenes to survive and persist in the human host, often in spite of antibiotic therapy, remain poorly characterized. Therefore, the determination of culture conditions for long-term studies is crucial to advancement in this field. Stationary cultures of S. pyogenes strain NZ131 and its spontaneous small-colony variant OK171 were found to survive in rich medium for less than 2 weeks, and this inability to survive resulted from the acidification of the medium to below pH 5.5, which the cells did not tolerate for longer than 6-7 days. The growth of NZ131 resulted in acidification of the culture to below pH 5.5 by the onset of stationary phase, and the loss of viability occurred in a linear fashion. These results were also found to be true for M49 strain CS101 and for M1 strain SF370. The S. pyogenes strains could be protected from killing by the addition of a buffer that stabilized the pH of the medium at pH 6.5, ensuring bacterial survival to at least 70 days. By contrast, increasing the glucose added to the medium accelerated the loss of culture viability in strain NZ131 but not OK171, suggesting that the small-colony variant is altered in glucose uptake or metabolism. Similarly, acidification of the medium prior to inoculation or at the middle of exponential phase resulted in growth inhibition of all strains. These results suggest that control of the pH is crucial for establishing long-term cultures of S. pyogenes.
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Affiliation(s)
- Dragutin J Savic
- Department of Pharmaceutical Sciences, The University of Oklahoma College of Pharmacy, PO Box 26901, Oklahoma City, OK 73190, USA
| | - William M McShan
- Department of Pharmaceutical Sciences, The University of Oklahoma College of Pharmacy, PO Box 26901, Oklahoma City, OK 73190, USA
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Cutaneous Manifestations of Infectious Diseases. ATLAS OF DERMATOLOGY IN INTERNAL MEDICINE 2012. [PMCID: PMC7178861 DOI: 10.1007/978-1-4614-0688-4_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Skin infections account for a significant portion of dermatologic diseases. Infections of the skin and subcutaneous tissues are highly diverse in respect to incidence, etiologic organisms, and clinical manifestations. Most cases are potentially treatable, thus, it is vital for the clinician to become familiar with the cutaneous expression of local and systemic processes. This chapter covers the clinical presentation, diagnosis, and treatment of the most common bacterial, viral, and fungal mucocutaneous infections encountered in internal medicine.
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Farmand S, Henneke P, Hufnagel M, Berner R. Significant decline in the erythromycin resistance of group A streptococcus isolates at a German paediatric tertiary care centre. Eur J Clin Microbiol Infect Dis 2011; 31:707-10. [DOI: 10.1007/s10096-011-1362-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2011] [Accepted: 07/14/2011] [Indexed: 11/25/2022]
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21
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Willems RJL, Hanage WP, Bessen DE, Feil EJ. Population biology of Gram-positive pathogens: high-risk clones for dissemination of antibiotic resistance. FEMS Microbiol Rev 2011; 35:872-900. [PMID: 21658083 DOI: 10.1111/j.1574-6976.2011.00284.x] [Citation(s) in RCA: 157] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Infections caused by multiresistant Gram-positive bacteria represent a major health burden in the community as well as in hospitalized patients. Staphylococcus aureus, Enterococcus faecalis and Enterococcus faecium are well-known pathogens of hospitalized patients, frequently linked with resistance against multiple antibiotics, compromising effective therapy. Streptococcus pneumoniae and Streptococcus pyogenes are important pathogens in the community and S. aureus has recently emerged as an important community-acquired pathogen. Population genetic studies reveal that recombination prevails as a driving force of genetic diversity in E. faecium, E. faecalis, S. pneumoniae and S. pyogenes, and thus, these species are weakly clonal. Although recombination has a relatively modest role driving the genetic variation of the core genome of S. aureus, the horizontal acquisition of resistance and virulence genes plays a key role in the emergence of new clinically relevant clones in this species. In this review, we discuss the population genetics of E. faecium, E. faecalis, S. pneumoniae, S. pyogenes and S. aureus. Knowledge of the population structure of these pathogens is not only highly relevant for (molecular) epidemiological research but also for identifying the genetic variation that underlies changes in clinical behaviour, to improve our understanding of the pathogenic behaviour of particular clones and to identify novel targets for vaccines or immunotherapy.
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Affiliation(s)
- Rob J L Willems
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands.
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22
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Emergence of erythromycin- and clindamycin-resistant Streptococcus pyogenes emm 90 strains in Hawaii. J Clin Microbiol 2010; 49:439-41. [PMID: 21068284 DOI: 10.1128/jcm.02208-10] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We identified 12 erythromycin- and clindamycin-resistant emm 90 group A streptococcus (GAS) isolates during a retrospective invasive disease survey in Hawaii. A comparison with 20 type-matched isolates showed all resistant isolates to be emm 90.4b with the constitutive or inducible macrolide-lincosamide-streptogramin B resistance phenotype (cMLS(B) or iMLS(B)). All isolates had the same pulsed-field gel electrophoresis (PFGE) pattern, suggesting clonal spread.
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23
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Hotomi M, Billal DS, Togawa A, Ikeda Y, Takei S, Kono M, Ogami M, Ubukata K, Sugita R, Fujihara K, Yamanaka N. Distribution of fibronectin-binding protein genes (prtF1 and prtF2) and streptococcal pyrogenic exotoxin genes (spe) among Streptococcus pyogenes in Japan. J Infect Chemother 2009; 15:367-73. [PMID: 20012726 DOI: 10.1007/s10156-009-0724-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Accepted: 08/06/2009] [Indexed: 10/20/2022]
Abstract
Two hundred and seventy-two strains of Streptococcus pyogenes isolated from patients with invasive and noninvasive infections in Japan were evaluated for the prevalence of fibronectin-binding protein genes (prtF1 and prtF2). The possible associations of the genes with streptococcal pyrogenic exotoxin genes, macrolide resistance genes, and emm types were also evaluated. Overall, about 50% of S. pyogenes isolates carried fibronectin-binding protein genes. The prevalence of the prtF1 gene was significantly higher among isolates from noninvasive infections (71.4%) than among isolates from invasive infections (30.8%; P = 0.0037). Strains possessing both the prtF1 and prtF2 genes were more likely to be isolates from noninvasive infections than isolates from invasive infections (50.6% vs 15.4%; P = 0.019). S. pyogenes isolates with streptococcus pyrogenic exotoxin genes (speA and speZ) were more common among isolates without fibronectin-binding protein genes. The speC gene was more frequently identified among isolates with fibronectin-binding protein genes (P = 0.05). Strains belonging to emm75 or emm12 types more frequently harbored macrolide resistance genes than other emm types (P = 0.0094 and P = 0.043, respectively). Strains carrying more than one repeat at the RD2 region of the prtF1 gene and the FBRD region of the prtF2 gene were more prevalent among strains with macrolide resistance genes than among strains negative for macrolide resistance genes. These genes (i.e., the prtF1, prtF2, and spe genes) may enable host-bacteria interaction, and internalization in the host cell, but may not enable infection complications such as invasive diseases.
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Affiliation(s)
- Muneki Hotomi
- Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8509, Japan
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Macrolide resistance in Streptococcus pyogenes: prevalence, resistance determinants, and emm types. Diagn Microbiol Infect Dis 2009; 64:295-9. [DOI: 10.1016/j.diagmicrobio.2009.03.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 02/25/2009] [Accepted: 03/05/2009] [Indexed: 11/21/2022]
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25
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Princivalli M, Paoletti C, Magi G, Palmieri C, Ferrante L, Facinelli B. Lactobacillus rhamnosusGG inhibits invasion of cultured human respiratory cells byprtF1-positive macrolide-resistant group A streptococci. Lett Appl Microbiol 2009; 48:368-72. [DOI: 10.1111/j.1472-765x.2008.02540.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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26
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27
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Antibiotic Resistance of Non-Pneumococcal Streptococci and Its Clinical Impact. ANTIMICROBIAL DRUG RESISTANCE 2009. [PMCID: PMC7122742 DOI: 10.1007/978-1-60327-595-8_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Viridans streptococci (VGS) form a phylogenetically heterogeneous group of species belonging to the genus Streptococcus (1). However, they have some common phenotypic properties. They are alfa- or non-haemolytic. They can be differentiated from S. pneumoniae by resistance to optochin and the lack of bile solubility (2). They can be differentiated from the Enterococcus species by their inability to grow in a medium containing 6.5% sodium chloride (2). Earlier, so-called nutritionally variant streptococci were included in the VGS but based on the molecular data they have now been removed to a new genus Abiotrophia (3) and are not included in the discussion below. VGS belong to the normal microbiota of the oral cavities and upper respiratory tracts of humans and animals. They can also be isolated from the female genital tract and all regions of the gastrointestinal tract (2, 3). Several species are included in VGS and are listed elsewhere (2, 3). Clinically the most important species belonging to the VGS are S. mitis, S. sanguis and S. oralis.
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Luca-Harari B, Straut M, Cretoiu S, Surdeanu M, Ungureanu V, van der Linden M, Jasir A. Molecular characterization of invasive and non-invasive Streptococcus pyogenes isolates from Romania. J Med Microbiol 2008; 57:1354-1363. [DOI: 10.1099/jmm.0.2008/001875-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In 2002, the Romanian National Reference Laboratory was invited to join the Strep-EURO project to study invasive Streptococcus pyogenes infections. During 2003 and 2004, a total of 33 isolates recovered from invasive disease were received from eight Romanian counties. For comparison, 102 isolates from non-invasive disease, as well as a collection of 12 old invasive strains (isolated between 1967 and 1980) were included. All isolates were characterized by several methods: T and emm typing, presence of the fibronectin-binding protein F1 gene (prtF1), serum opacity factor (sof), and superantigen (SAg) genes (speA, speB, speC, speF, speG, speH, ssa and smeZ). The recent invasive isolates exhibited 19 emm-types, of which emm1, emm81, emm76, emm49 and emm78 covered 57 % of the strains. Furthermore, multilocus sequence typing analysis revealed nine new sequence types, corresponding to emm types 1, 12, 49, 81, 92, 100, 106 and 119. The non-invasive isolates comprised 24 different emm types with a predominance of emm1 and 12; the old invasive strains were of eight emm types, of which four were unique for this group. All isolates harboured speB and speF; smeZ was detected in all invasive strains, except for the emm49 and emm81 isolates. The majority of isolates from carriers, and patients with pharyngitis were prtF1 positive, most of these (14 strains) being emm12. High tetracycline resistance rates were noted among both invasive and control isolates (54 % and 35 %, respectively), whereas macrolide resistance rates were low (3 % and 5 %, respectively). Active and continuing surveillance is required to provide an accurate assessment of the disease burden and to provide epidemiological data on the character of isolates in Romania.
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Affiliation(s)
- Bogdan Luca-Harari
- Institute of Laboratory Medicine, Section of Medical Microbiology, Lund University, Lund, Sweden
| | - Monica Straut
- National Institute of Research and Development for Microbiology and Immunology, Cantacuzino, Bucharest, Romania
| | - Silvia Cretoiu
- National Institute of Research and Development for Microbiology and Immunology, Cantacuzino, Bucharest, Romania
| | - Maria Surdeanu
- National Institute of Research and Development for Microbiology and Immunology, Cantacuzino, Bucharest, Romania
| | - Vasilica Ungureanu
- National Institute of Research and Development for Microbiology and Immunology, Cantacuzino, Bucharest, Romania
| | - Mark van der Linden
- German National Reference Center for Streptococci, Department of Medical Microbiology, University Hospital RWTH Aachen, Aachen, Germany
| | - Aftab Jasir
- Department of Clinical Microbiology and Immunology, Lund University Hospital (USIL), Lund, Sweden
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29
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A foodborne outbreak of a group A streptococcal infection in a Japanese university hospital. Eur J Clin Microbiol Infect Dis 2008; 28:305-8. [DOI: 10.1007/s10096-008-0614-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Accepted: 07/28/2008] [Indexed: 11/27/2022]
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30
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Oliver MA, García-Rey C, Bosch R, Albertí S. Evaluation of the ability of erythromycin-resistant and -susceptible pharyngeal group A Streptococcus isolates from Spain to enter and persist in human keratinocytes. J Med Microbiol 2008; 56:1485-1489. [PMID: 17965349 DOI: 10.1099/jmm.0.47203-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The macrolide-resistance rate among group A Streptococcus (GAS) isolates has increased in some European countries. To investigate the reasons for this increase, the ability of 60 erythromycin-resistant and 61 erythromycin-susceptible, genetically unrelated, pharyngeal GAS isolates from Spain to enter and persist within human keratinocytes was evaluated. It was observed that erythromycin resistance was associated with the presence of prtF1, a gene related to invasiveness, whereas no association was observed with the ability to enter human keratinocytes. However, the ability to enter human keratinocytes was not associated with the presence of prtF1 or with the emm type, suggesting that interaction with keratinocytes depends on several characteristics of the isolate. Almost all strains (95.9 %) were capable of persisting within human keratinocytes. However, most of them (91.7 %) exhibited a decline in viability over time. Interestingly, the ability to persist within keratinocytes protected from the action of the beta-lactams was higher among erythromycin-resistant isolates and correlated with their ability to avoid the induction of cellular lysis. These observations suggest that if the carrier state results from intracellular GAS survival, the association between erythromycin resistance and intracellular persistence may represent a serious problem for the eradication of these isolates.
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Affiliation(s)
- Maria A Oliver
- Institut Universitari d'Investigacions en Ciències de la Salut (IUNICS), Universitat de les Illes Balears (UIB), Palma de Mallorca, Spain
| | - César García-Rey
- Departamento Médico, GlaxoSmithKline SA, Tres Cantos, Madrid, Spain
| | - Rafael Bosch
- Área de Microbiología, Departamento de Biologia, Universitat de les Illes Balears (UIB), Palma de Mallorca, Spain
| | - Sebastián Albertí
- Institut Universitari d'Investigacions en Ciències de la Salut (IUNICS), Universitat de les Illes Balears (UIB), Palma de Mallorca, Spain
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Tart AH, Walker MJ, Musser JM. New understanding of the group A Streptococcus pathogenesis cycle. Trends Microbiol 2007; 15:318-25. [PMID: 17524649 DOI: 10.1016/j.tim.2007.05.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Revised: 03/26/2007] [Accepted: 05/09/2007] [Indexed: 10/23/2022]
Abstract
Group A Streptococcus (GAS) has long been recognized as a human pathogen causing an exceptionally broad range of infections. Despite intense research, however, the molecular mechanisms of GAS disease remain unclear. Recently, many important discoveries have been made that shed light on GAS pathogenesis and open exciting avenues for future research. Advances in genome sequencing, microarray technology and proteomic analysis, in combination with the development of more suitable animal models, have markedly increased our knowledge of the mechanisms underlying GAS pathogenesis. The information gained from these studies will translate into improved diagnostics and new targets for therapeutic drugs and vaccines.
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Affiliation(s)
- Anne H Tart
- Center for Molecular and Translational Human Infectious Diseases Research, The Methodist Hospital Research Institute, and Department of Pathology, The Methodist Hospital, 6565 Fannin Street B490, Houston, TX 77030, USA
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Jaggi P, Beall B, Rippe J, Tanz RR, Shulman ST. Macrolide resistance and emm type distribution of invasive pediatric group A streptococcal isolates: three-year prospective surveillance from a children's hospital. Pediatr Infect Dis J 2007; 26:253-5. [PMID: 17484224 DOI: 10.1097/01.inf.0000256761.10463.29] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Macrolide-resistant group A streptococci (GAS) have been suggested to have more invasive potential. An M protein-based GAS vaccine is currently in development. We sought to define the GAS emm types and macrolide resistance rates among pediatric invasive GAS isolates collected prospectively during a recent 40-month period at our children's hospital. PATIENTS AND METHODS We prospectively identified and collected GAS isolates from patients with invasive GAS disease (isolates from normally sterile sites). Susceptibility assays for erythromycin and clindamycin were performed by E-test. emm typing was performed by the Centers for Disease Control and Prevention. Clinical characteristics of patients were identified by chart review. RESULTS A total of 37 patient isolates were identified, of which 35 isolates were able to be characterized. Four patients had underlying illness. No macrolide resistance was detected among the isolates. The most common emm types causing invasive disease were emm 1.0 (43%) and emm 12.0 (11.1%). CONCLUSIONS In this group of 35 invasive GAS isolates, no cases of macrolide resistance were found. emm type 1 accounted for the highest percentage of invasive disease, followed by emm type 12. The type-specific GAS M protein-based vaccine currently in development includes the emm types of 33 of 35 (94%) of the invasive emm types in this series.
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Affiliation(s)
- Preeti Jaggi
- Columbus Children's Hospital, Columbus, OH, USA.
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Baldassarri L, Creti R, Imperi M, Recchia S, Pataracchia M, Orefici G. Detection of genes encoding internalization-associated proteins in Streptococcus pyogenes isolates from patients with invasive diseases and asymptomatic carriers. J Clin Microbiol 2007; 45:1284-7. [PMID: 17287324 PMCID: PMC1865825 DOI: 10.1128/jcm.02119-06] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 161 Streptococcus pyogenes isolates from patients with invasive infections or from asymptomatic carriers were examined for genes (prtF1, prtF2, and fba) coding for fibronectin-binding proteins to evaluate their involvement in the pathogenesis of different streptococcal manifestations. We found no significant differences in the presence of these three genes between the two groups. Overall, the prtF2 gene was present in similar percentages among strains from both sources (61% versus 63%). Strains carrying the gene fba were slightly more common among those isolated from asymptomatic carriers (72.6% versus 65%). Also, the prtF1 gene was present in a higher, but not significant, percentage among strains from throat swabs than among isolates from invasive infections (75% versus 64.9%). However, this more detailed characterization of the genes encoding fibronectin-binding proteins allowed us to identify a strong association of genes of the erm class, coding for macrolide resistance, with prtF1 and prtF2 rather than with prtF1 alone. Since macrolide resistance was significantly associated with throat swab isolates, it may be hypothesized that proteins coded by prtF1 and prtF2 genes may be synergic in providing support for cell invasion and/or colonizing or persistence efficiency.
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Affiliation(s)
- Lucilla Baldassarri
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
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Podbielski A. Flexible architecture of the Streptococcus pyogenes FCT genome region: finally the clue for understanding purulent skin diseases and long-term persistence? J Bacteriol 2006; 189:1181-4. [PMID: 17142401 PMCID: PMC1797344 DOI: 10.1128/jb.01748-06] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Andreas Podbielski
- Department of Medical Microbiology, Virology and Hygiene, University Hospital, Schillingallee 70, D-18057 Rostock, Germany.
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35
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Robinson DA, Sutcliffe JA, Tewodros W, Manoharan A, Bessen DE. Evolution and global dissemination of macrolide-resistant group A streptococci. Antimicrob Agents Chemother 2006; 50:2903-11. [PMID: 16940080 PMCID: PMC1563541 DOI: 10.1128/aac.00325-06] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Macrolide-resistant group A streptococci (MRGAS) have been recovered from many countries worldwide. However, the strain typing information that is available has been insufficient for estimating the total number of macrolide-resistant clones, their geographic distributions, and their evolutionary relationships. In this study, sequence-based strain typing was used to characterize 212 MRGAS isolates from 34 countries. Evaluation of clonal complexes, emm type, and resistance gene content [erm(A), erm(B), mef(A), and undefined] indicate that macrolide resistance was acquired by GAS organisms via > or independent genetic events. In contrast to other collections of mostly susceptible GAS, genetic diversification of MRGAS clones has occurred primarily by mutation rather than by recombination. Twenty-two MRGAS clonal complexes were recovered from more than one continent; intercontinental strains represent nearly 80% of the MRGAS isolates under study. The findings suggest that horizontal transfer of macrolide resistance genes to numerous genetic backgrounds and global dissemination of resistant clones and their descendants are both major components of the present-day macrolide resistance problem found within this species.
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Affiliation(s)
- D Ashley Robinson
- Department of Microbiology and Immunology, New York Medical College, Valhalla, NY 10595, USA
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36
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Palmieri C, Vecchi M, Littauer P, Sundsfjord A, Varaldo PE, Facinelli B. Clonal spread of macrolide- and tetracycline-resistant [erm(A) tet(O)] emm77 Streptococcus pyogenes isolates in Italy and Norway. Antimicrob Agents Chemother 2006; 50:4229-30. [PMID: 17043129 PMCID: PMC1693999 DOI: 10.1128/aac.00943-06] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Spinaci C, Magi G, Varaldo PE, Facinelli B. Persistence of erythromycin-resistant group a streptococci in cultured respiratory cells. Pediatr Infect Dis J 2006; 25:880-3. [PMID: 17006280 DOI: 10.1097/01.inf.0000238136.63851.4a] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND A significant association between erythromycin resistance and ability of bacteria to enter human respiratory cells has been documented in group A streptococci (GAS) isolated in Italy from children with pharyngitis. The occurrence of strains combining cell invasiveness with erythromycin resistance raised serious concern because they could escape penicillin by virtue of intracellular location and macrolides by virtue of resistance, resulting in difficulty in eradication. METHODS Thirty-one pharyngeal cell-invasive, erythromycin-resistant (ER) GAS, representing that many clones recently identified among Italian GAS carrying the internalization-related gene prtF1, were investigated for intracellular persistence inside cultured respiratory cells (A549) by means of a survival assay and by staining and polymerase chain reaction assays on infected cells. RESULTS All tested ER GAS could be recovered in culture from infected cells 24 hours from infection with logarithms exceeding 4.0 (4 strains). The highest survival rate (>5.0) was exhibited by strain SP1900 [erm(A)/iMLS-B; high-level erythromycin resistance [minimum inhibitory concentration, > or =128 microg/mL)], the most widespread clone, which was cultivable from infected cells up to day 5. As long as SP1900-infected cells could be maintained in culture, the presence of multiple cocci inside cells was consistently revealed by microscopy. During the same time, DNA sequences internal to both genes prtF1 and erm(A) continued to be amplified by polymerase chain reaction. CONCLUSIONS These results suggest that the ER GAS are capable of persisting in human respiratory cells. This might contribute to clinical problems such as relapsing infection and persistent carriage despite antibiotic treatment and might have facilitated the widespread diffusion of ER GAS in Italy.
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Affiliation(s)
- Cinzia Spinaci
- Institute of Microbiology and Biomedical Sciences, Marche Polytechnic University Medical School, Ancona, Italy
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38
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Nir-Paz R, Block C, Shasha D, Korenman Z, Gorodnitzky Z, Jaffe J, Ron M, Michael-Gayego A, Cohen-Poradosu R, Shapiro M, Moses AE. Macrolide, lincosamide and tetracycline susceptibility and emm characterisation of invasive Streptococcus pyogenes isolates in Israel. Int J Antimicrob Agents 2006; 28:313-9. [PMID: 16973336 DOI: 10.1016/j.ijantimicag.2006.07.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2006] [Revised: 05/29/2006] [Accepted: 05/31/2006] [Indexed: 11/29/2022]
Abstract
Group A beta-haemolytic streptococcus (GAS) causes a variety of infections, including life-threatening illnesses. Although the species is uniformly penicillin susceptible, resistance to other antibiotics is becoming more common. We studied the prevalence of resistance and associated factors in a nationwide, prospective, population-based study of invasive infections in Israel. Isolates were collected in collaboration with 24 hospitals in Israel during 1996-1999. Minimal inhibitory concentrations (MICs) of erythromycin (ERY), clindamycin (CLI) and tetracycline (TET) were determined as well as ERY and TET resistance phenotypes and genotypes. Five hundred isolates were examined: 136 (27.2%) were not susceptible to TET, 10 (2.0%) to ERY and 5 (1%) to CLI. ERY resistance was associated with emm types 12 and 83 (P<0.001 for both). MICs of TET had a bimodal distribution distinguishing sensitive and resistant populations. Non-susceptibility to TET was mainly due to the presence of tet(M) and was associated with T types 3, 3/13/B3624 and 9 and emm types 9, 33, 64, 73, 74, 76, 77 and 83. TET susceptibility was associated with T types 1, 2 and 11, emm types 1-4, 11, 12, 22, 26 and 75 and the presence of speA and speC. In Israel, resistance of invasive GAS isolates to ERY remains low and is associated with specific T and emm types, as is TET resistance. TET resistance is less frequent than previously reported in Israel and is associated with a lower prevalence of speA and speC.
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Affiliation(s)
- Ran Nir-Paz
- Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center, P.O. Box 12000, Jerusalem, Israel
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39
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Baldassarri L, Creti R, Recchia S, Imperi M, Facinelli B, Giovanetti E, Pataracchia M, Alfarone G, Orefici G. Therapeutic failures of antibiotics used to treat macrolide-susceptible Streptococcus pyogenes infections may be due to biofilm formation. J Clin Microbiol 2006; 44:2721-7. [PMID: 16891483 PMCID: PMC1594624 DOI: 10.1128/jcm.00512-06] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2006] [Revised: 04/24/2006] [Accepted: 06/05/2006] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pyogenes infections often fail to respond to antibiotic therapy, leading to persistent throat carriage and recurrent infections. Such failures cannot always be explained by the occurrence of antibiotic resistance determinants, and it has been suggested that S. pyogenes may enter epithelial cells to escape antibiotic treatment. We investigated 289 S. pyogenes strains isolated from different clinical sources to evaluate their ability to form biofilm as an alternative method to escape antibiotic treatment and host defenses. Up to 90% of S. pyogenes isolates, from both invasive and noninvasive infections, were able to form biofilm. Specific emm types, such as emm6, appeared to be more likely to produce biofilm, although variations within strains belonging to the same type might suggest biofilm formation to be a trait of individual strains rather than a general attribute of a serotype. Interestingly, erythromycin-susceptible isolates formed a significantly thicker biofilm than resistant isolates (P < 0.05). Among resistant strains, those carrying the erm class determinants formed a less organized biofilm than the mef(A)-positive strains. Also, prtF1 appeared to be negatively associated with the ability to form biofilm (P < 0.01). Preliminary data on a selection of strains indicated that biofilm-forming isolates entered epithelial cells with significantly lower efficiency than biofilm-negative strains. We suggest that prtF1-negative macrolide-susceptible or mef(A)-carrying isolates, which are poorly equipped to enter cells, may use biofilm to escape antimicrobial treatments and survive within the host. In this view, biofilm formation by S. pyogenes could be responsible for unexplained treatment failures and recurrences due to susceptible microorganisms.
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Affiliation(s)
- Lucilla Baldassarri
- Reparto di Malattie Batteriche Respiratorie e Sistemiche, Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Roma, Italy.
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40
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Bianco S, Allice T, Zucca M, Savoia D. Survey of phenotypic and genetic features of streptococcus pyogenes strains isolated in Northwest Italy. Curr Microbiol 2005; 52:33-9. [PMID: 16391999 DOI: 10.1007/s00284-005-0067-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Accepted: 08/22/2005] [Indexed: 11/29/2022]
Abstract
Streptococcus pyogenes (group A Streptococcus [GAS]) is an important pathogen whose virulence is related to the production of exotoxins and the presence of particular surface components. One hundred eighty-two GAS strains were collected in northwestern Italy between 1994 and 2002 and analyzed for phenotypic characteristics (opacity factor, proteolyic activity, and antimicrobial susceptibility) and by polymerase chain reaction for the presence of genes responsible for the production of exotoxins implicated in pathogenesis speA and speF and of prtF(1) (encoding fibronectin-binding protein F1). All strains were speF positive and 19.2% were speA positive and prtF(1) negative, whereas the prtF(1) gene was identified in 39.5% of the other strains. Of these, approximately half revealed the same pulse-field gel electrophoresis (PFGE) pattern but differed in both speA gene and macrolide resistance.
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Affiliation(s)
- Simona Bianco
- Dipartimento di Scienze Cliniche e Biologiche, Università di Torino, c/o Ospedale S. Luigi Gonzaga, Regione Gonzole, 10043 Orbassano (TO), Italy
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41
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Abstract
The emergence of bacterial resistance to commonly used antibiotics is not new. In this review we have tried to cover the ever increasing problems facing the treatment and containment of bacterial skin infections. We have tried to give an overview of the varied mechanisms by which bacteria gain and spread antimicrobial resistance, whilst dealing with the patterns of resistance exhibited by some of the commonly encountered organisms. Where there is evidence, we have formulated an approach on how to tackle antibiotic resistance. Where there is a lack of evidence we have formulated what we perceive to be appropriate guidelines.
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Affiliation(s)
- G Perera
- Department of Dermatology, King's College Hospital, Denmark Hill, Camberwell, London, SE5 9RS, UK.
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42
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Haller M, Fluegge K, Arri SJ, Adams B, Berner R. Association between resistance to erythromycin and the presence of the fibronectin binding protein F1 gene, prtF1, in Streptococcus pyogenes isolates from German pediatric patients. Antimicrob Agents Chemother 2005; 49:2990-3. [PMID: 15980381 PMCID: PMC1168679 DOI: 10.1128/aac.49.7.2990-2993.2005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 301 German pediatric group A streptococcus isolates were screened for the presence of macrolide resistance and the fibronectin binding protein F1 gene (prtF1) encoding an adhesin and cell invasiveness protein. The prtF1 gene was present significantly more often among macrolide-resistant isolates. The majority of these were not clonally related.
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Affiliation(s)
- Maria Haller
- Department of Pediatrics and Adolescent Medicine, University Hospital of Freiburg, Mathildenstrasse 1, 79106 Freiburg, Germany
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43
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Wood DN, Chaussee MA, Chaussee MS, Buttaro BA. Persistence of Streptococcus pyogenes in stationary-phase cultures. J Bacteriol 2005; 187:3319-28. [PMID: 15866916 PMCID: PMC1111994 DOI: 10.1128/jb.187.10.3319-3328.2005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
In addition to causing fulminant disease, Streptococcus pyogenes may be asymptomatically carried between recurrent episodes of pharyngitis. To better understand streptococcal carriage, we characterized in vitro long-term stationary-phase survival (>4 weeks) of S. pyogenes. When grown in sugar-limited Todd-Hewitt broth, S. pyogenes cells remained culturable for more than 1 year. Both Todd-Hewitt supplemented with excess glucose and chemically defined medium allowed survival for less than 1 week. After 4 weeks of survival in sugar-limited Todd-Hewitt broth, at least 10(3) CFU per ml remained. When stained with fluorescent live-dead viability stain, there were a number of cells with intact membranes that were nonculturable. Under conditions that did not support persistence, these cells disappeared 2 weeks after loss of culturability. In persistent cultures, these may be cells that are dying during cell turnover. After more than 4 weeks in stationary phase, the culturable cells formed two alternative colony phenotypes: atypical large colonies and microcolonies. Protein expression in two independently isolated microcolony strains, from 14-week cultures, was examined by use of two-dimensional electrophoresis. The proteomes of these two strains exhibited extensive changes compared to the parental strain. While some of these changes were common to the two strains, many of the changes were unique to a single strain. Some of the common changes were in metabolic pathways, suggesting a possible alternate metabolism for the persisters. Overall, these data suggest that under certain in vitro conditions, S. pyogenes cells can persist for greater than 1 year as a dynamic population.
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Affiliation(s)
- Daniel N Wood
- Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA
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44
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Shulman ST, Tanz RR. Streptococcal otitis media: from epidemiology to pathogenesis. Clin Infect Dis 2005; 41:42-4. [PMID: 15937761 DOI: 10.1086/430609] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2005] [Accepted: 03/25/2005] [Indexed: 11/03/2022] Open
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45
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Klaassen CHW, Mouton JW. Molecular detection of the macrolide efflux gene: to discriminate or not to discriminate between mef(A) and mef(E). Antimicrob Agents Chemother 2005; 49:1271-8. [PMID: 15793097 PMCID: PMC1068581 DOI: 10.1128/aac.49.4.1271-1278.2005] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Corné H W Klaassen
- Department of Medical Microbiology and Infectious Diseases, Canisius Wilhelmina Hospital, Nijmegen 6532 SZ, The Netherlands.
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46
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Giovanetti E, Brenciani A, Vecchi M, Manzin A, Varaldo PE. Prophage association of mef(A) elements encoding efflux-mediated erythromycin resistance in Streptococcus pyogenes. J Antimicrob Chemother 2005; 55:445-51. [PMID: 15772148 DOI: 10.1093/jac/dki049] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES To compare different mef(A) elements of Streptococcus pyogenes for a possible chimeric genetic nature, i.e. a transposon inserted into a prophage. METHODS Eleven S. pyogenes isolates with efflux-mediated erythromycin resistance were used. The isolates were typed using several genotypic approaches. Gene detection was performed by PCR using specific primer pairs. The mef(A) elements of the test strains were induced with mitomycin C and phage DNA was extracted. Induction was monitored by PCR using primers targeting mef(A). RESULTS Six tetracycline-susceptible isolates had PCR evidence of all of the eight open reading frames (ORFs) of the Tn1207.1 element; their mef(A) element was consistent with the Tn1207.3 element in four isolates and with the 58.8 kb chimeric element in two. Five tetracycline-resistant isolates had no PCR evidence of orf1 and orf2 and showed variable patterns as to orf3, orf7, and orf8. Three ORFs placed along the conserved region downstream of Tn1207.1 in the 58.8 kb mef(A) chimeric element were detected in the six tetracycline-susceptible, but not in the five tetracycline-resistant isolates. Induction assays with mitomycin C demonstrated that the mef(A) elements of all strains tested were present in culture supernatants in a DNAse-resistant form, such as a phage capsid. CONCLUSIONS All recognized mef(A) elements of S. pyogenes appear to be prophage-associated. Whereas the two elements detected in tetracycline-susceptible isolates (Tn1207.3 and the 58.8 kb one) were apparently inserted into the same prophage, the tet(O)-mef(A) element was inserted into a different prophage. Phage transfer is likely to play a critical role in the dissemination of erythromycin resistance in S. pyogenes populations.
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Affiliation(s)
- Eleonora Giovanetti
- Istituto di Microbiologia e Scienze Biomediche, Università Politecnica delle Marche, 60131 Ancona, Italy
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47
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Cocuzza CE, Lanzafame A, Sisto F, Broccolo F, Mattina R. Prevalence of the internalization-associated gene prtF1 in a bacterial population of Streptococcus pyogenes isolated from children with acute pharyngotonsillitis before and after antibiotic therapy. Microb Drug Resist 2005; 10:264-8. [PMID: 15383172 DOI: 10.1089/mdr.2004.10.264] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The prevalence of the internalization-associated prtF1 gene was studied in 837 isolates of Streptococcus pyogenes obtained from 713 pediatric patients presenting with acute pharyngotonsillitis before and after antibiotic therapy. Its association with macrolide resistance and with bacteriological treatment failure was determined. The bacterial population isolated from baseline pharyngeal swabs showed an overall prtF1 positivity rate of 33%. A higher prtF1 positivity was found among erythromycin-resistant strains (45%) showing, however, marked differences between the inducible (iMLS), constitutive (cMLS), and efflux pump (M) resistance phenotypes. The prevalence was statistically higher (p < 0.001) in strains belonging to iMLS (84%) and cMLS (67%) phenotypes as compared to the M phenotype (15%). Interestingly, the prevalence of the prtF1 gene was significantly lower (p = 0.04) in strains belonging to M resistance phenotype as compared to erythromycin-susceptible strains (28%). Failed bacterial eradication was demonstrated in 124 patients. The prtF1 positivity rate remained unchanged in strains isolated before and after therapy in patients treated with macrolides (9/54). On the other hand, the positivity rate for the prtF1 gene was significantly higher (p = 0.015) in strains isolated after therapy with beta-lactams (21/70) as compared to baseline isolates (6/70), indicating a differential selection imposed on the organism by these agents. Finally, a high overall eradication rate (88%) of prtF1-positive isolates, belonging to both the erythromycin-susceptible and -resistant phenotypes, was demonstrated following macrolide treatment.
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Affiliation(s)
- C E Cocuzza
- Department of Clinical Medicine, Prevention and Biotechnologies, University of Milano-Bicocca, Monza, Italy.
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48
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Tanz RR, Shulman ST, Shortridge VD, Kabat W, Kabat K, Cederlund E, Rippe J, Beyer J, Doktor S, Beall BW. Community-Based Surveillance in the United States of Macrolide-Resistant Pediatric Pharyngeal Group A Streptococci during 3 Respiratory Disease Seasons. Clin Infect Dis 2004; 39:1794-801. [PMID: 15578402 DOI: 10.1086/426025] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2004] [Accepted: 08/17/2004] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND In 2001, a total of 48% of pharyngeal group A streptococci (GAS) from Pittsburgh children were macrolide resistant. We assessed macrolide resistance, resistance genes, and emm types among GAS in the United States. METHODS In prospective, multicenter, community-based surveillance of pharyngeal GAS recovered from children 3-18 years old during 3 respiratory seasons (the 2000-2001 season, the 2001-2002 season, and the 2002-2003 season), GAS were tested for macrolide resistance and underwent emm gene sequencing. Macrolide-resistant GAS were tested for resistance to clindamycin, and resistance genes were determined. RESULTS Erythromycin resistance was observed in 4.4% of isolates from the 2000-2001 season, 4.3% from the 2001-2002 season, and 3.8% from the 2002-2003 season (P=.80). Clindamycin resistance was found in 1.04% of isolates; annual rates of clindamycin resistance were stable (P=.75). The predominant resistance genotype each year was mef A (65%-76.9%; overall, 70.3%). Resistant isolates included strains representing 8-11 different emm types each year. Heterogeneity of emm subtypes, resistance genes, and clindamycin resistance was evident among resistant isolates within some emm types. Geographic variability in resistance rates was present each year. CONCLUSIONS The macrolide resistance rate among pharyngeal GAS was <5% and was stable over the 3 seasons. However, rates varied among sites each year. There was no evidence of spread of a specific resistant clone, increasing clindamycin resistance, or escalation in median erythromycin MICs.
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Affiliation(s)
- Robert R Tanz
- Division of General Academic Pediatrics, Children's Memorial Hospital, Chicago, IL 60614, USA.
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49
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Brenciani A, Ojo KK, Monachetti A, Menzo S, Roberts MC, Varaldo PE, Giovanetti E. Distribution and molecular analysis of mef(A)-containing elements in tetracycline-susceptible and -resistant Streptococcus pyogenes clinical isolates with efflux-mediated erythromycin resistance. J Antimicrob Chemother 2004; 54:991-8. [PMID: 15563518 DOI: 10.1093/jac/dkh481] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES To analyse the distribution and molecular features of mef(A)-containing elements in a large collection of different Streptococcus pyogenes clinical isolates with efflux-mediated erythromycin resistance. To further characterize a tet(O)-mef(A) element. METHODS Gene detection was carried out by PCR using primers designed from established sequences or from sequences in this study. From a tet(O)-mef(A) element (approximately 60 kb), an 11 972 bp region including the tet(O) and mef(A) genes was sequenced. RESULTS In the tetracycline-susceptible isolates (n =28), the mef(A) gene was contained in a regular Tn1207.1 transposon (7.2 kb), which was inserted into one of two previously described elements, Tn1207.3 (approximately 52 kb) or a 58.8 kb chimeric element, both flanked by the comEC gene. In the tetracycline-resistant isolates (n =61), all of which carried the tet(O) gene, the mef(A) gene was part of a variable Tn1207.1-related transposon inserted into unique elements which contained the tet(O) gene approximately 2.3 to 5.5 kb upstream of the mef(A) gene and were not flanked by the comEC gene. In the Tn1207.1-like transposon of these tet(O)-mef(A) elements, only msr(D) (orf5) and a modified orf6, in addition to mef(A), were detected by PCR in all isolates tested; while orf1 and orf2 were always undetectable, orf3, orf7 and orf8 were found in variable percentages. In an orf3-positive element, sequencing identified four new open reading frames downstream of the tet(O) gene, followed by three short sequences with homology to sequences of the pneumococcal mega element. CONCLUSIONS The mef(A) gene is carried on different chromosomal genetic elements depending on whether the isolates are susceptible or resistant to tetracycline.
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Affiliation(s)
- Andrea Brenciani
- Institute of Microbiology and Biomedical Sciences, Marche Polytechnic University, 60131 Ancona, Italy
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Kreikemeyer B, Klenk M, Podbielski A. The intracellular status of Streptococcus pyogenes: role of extracellular matrix-binding proteins and their regulation. Int J Med Microbiol 2004; 294:177-88. [PMID: 15493828 DOI: 10.1016/j.ijmm.2004.06.017] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Streptococcus pyogenes (group A streptococci, GAS) is an important and exclusively human pathogen. Adherence to and internalization into host cells significantly contributes to the pathogenesis of GAS infections. The adherence mechanism is a two-step process in which host extracellular matrix (ECM) proteins act as prime targets. GAS may express more than a dozen different microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) that attach to fibronectin or collagen. One of them, protein F1/SfbI binds fibronectin and mediates adherence of GAS to host cells. Bound fibronectin acts as a bridging molecule towards host cell integrins, which in turn initialize the uptake process that leads to GAS internalization. In their safe intracellular niche GAS can persist protected from antibiotics and host defense, a scenario currently discussed in the context of treatment failure, asymptomatic GAS carriers and recurrent GAS infections. Patients with such low grade infections represent the main GAS reservoir from which the bacteria are spread in the general population. Due to their important function, expression of GAS MSCRAMMs is under control of several "stand alone" transcriptional regulators and two-component signal transduction systems. Several regulator genes are organized together with MSCRAMM genes on one of two potential pathogenicity islands, act together in a growth phase-dependent regulatory network and are expressed in a strain-specific manner. A detailed understanding of these mechanisms is crucial, since interference with MSCRAMM function alone or in conjunction with specific manipulations of regulators is an attractive goal for novel anti-infective strategies.
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Affiliation(s)
- Bernd Kreikemeyer
- Department of Medical Microbiology and Hospital Hygiene, University Hospital Rostock, Schillingallee 70, D-18055 Rostock, Germany.
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