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Braun SD, Asif M, Hassan L, Ul Haq I, Abbasi SA, Jamil B, Monecke S, Ehricht R, Mueller E, Syed MA. Analysis of carbapenem-resistant strains isolated in a tertiary care hospital in Rawalpindi, Pakistan, during the years 2016 and 2020. J Hosp Infect 2023; 141:187-189. [PMID: 37321411 DOI: 10.1016/j.jhin.2023.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 06/09/2023] [Indexed: 06/17/2023]
Affiliation(s)
- S D Braun
- Leibniz Institute of Photonic Technology Member of the Leibniz Center for Photonics in Infection Research (LPI), Jena, Germany; InfectoGnostics Research Campus, Jena, Germany.
| | - M Asif
- Department of Microbiology, University of Haripur, Haripur, Pakistan
| | - L Hassan
- Department of Microbiology, University of Haripur, Haripur, Pakistan
| | - I Ul Haq
- Department of Microbiology, University of Haripur, Haripur, Pakistan
| | - S A Abbasi
- Fauji Foundation Hospital, Rawalpindi, Pakistan
| | - B Jamil
- BJ Micro Lab, Rawalpindi, Pakistan
| | - S Monecke
- Leibniz Institute of Photonic Technology Member of the Leibniz Center for Photonics in Infection Research (LPI), Jena, Germany; InfectoGnostics Research Campus, Jena, Germany; Institute for Medical Microbiology and Virology, Dresden University Hospital, Dresden, Germany
| | - R Ehricht
- Leibniz Institute of Photonic Technology Member of the Leibniz Center for Photonics in Infection Research (LPI), Jena, Germany; InfectoGnostics Research Campus, Jena, Germany; Institute of Physical Chemistry, Friedrich-Schiller University, Jena, Germany
| | - E Mueller
- Leibniz Institute of Photonic Technology Member of the Leibniz Center for Photonics in Infection Research (LPI), Jena, Germany; InfectoGnostics Research Campus, Jena, Germany
| | - M A Syed
- Department of Microbiology, University of Haripur, Haripur, Pakistan.
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Aloba BK, Kinnevey PM, Monecke S, Brennan GI, O'Connell B, Blomfeldt A, McManus BA, Schneider-Brachert W, Tkadlec J, Ehricht R, Senok A, Bartels MD, Coleman DC. An emerging Panton-Valentine leukocidin-positive CC5-meticillin-resistant Staphylococcus aureus-IVc clone recovered from hospital and community settings over a 17-year period from 12 countries investigated by whole-genome sequencing. J Hosp Infect 2023; 132:8-19. [PMID: 36481685 DOI: 10.1016/j.jhin.2022.11.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 11/26/2022] [Indexed: 12/12/2022]
Abstract
BACKGROUND A novel Panton-Valentine leukocidin (PVL)-positive meticillin-resistant Staphylococcus aureus (MRSA) clonal complex (CC)5-MRSA-IVc ('Sri Lankan' clone) was recently described from Sri Lanka. Similar isolates caused a recent Irish hospital outbreak. AIM To investigate the international dissemination and diversity of PVL-positive CC5-MRSA-IVc isolates from hospital and community settings using whole-genome sequencing (WGS). METHODS Core-genome single nucleotide polymorphism (cgSNP) analysis, core-genome multi-locus sequence typing (cgMLST) and microarray-based detection of antimicrobial-resistance and virulence genes were used to investigate PVL-positive CC5-MRSA-IVc (N = 214 including 46 'Sri Lankan' clone) from hospital and community settings in 12 countries over 17 years. Comparators included 29 PVL-positive and 23 PVL-negative CC5/ST5-MRSA-I/II/IVa/IVc/IVg/V. RESULTS Maximum-likelihood cgSNP analysis grouped 209/214 (97.7%) CC5-MRSA-IVc into Clade I; average of 110 cgSNPs between isolates. Clade III contained the five remaining CC5-MRSA-IVc; average of 92 cgSNPs between isolates. Clade II contained seven PVL-positive CC5-MRSA-IVa comparators, whereas the remaining 45 comparators formed an outlier group. Minimum-spanning cgMLST analysis revealed a comparably low average of 57 allelic differences between all CC5/ST5-MRSA-IVc. All 214 CC5/ST5-MRSA-IVc were identified as 'Sri Lankan' clone, predominantly spa type t002 (186/214) with low population diversity and harboured a similar range of virulence genes and variable antimicrobial-resistance genes. All 214 Sri Lankan clone isolates and Clade II comparators harboured a 9616-bp chromosomal PVL-encoding phage remnant, suggesting both arose from a PVL-positive meticillin-susceptible ancestor. Over half of Sri Lankan clone isolates were from infections (142/214), and where detailed metadata were available (168/214), most were community associated (85/168). CONCLUSIONS Stable chromosomal retention of pvl may facilitate Sri-Lankan clone dissemination.
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Affiliation(s)
- B K Aloba
- Microbiology Research Unit, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland
| | - P M Kinnevey
- Microbiology Research Unit, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland
| | - S Monecke
- Leibniz Institute of Photonic Technology (IPHT), Jena, Germany; Institut für Medizinische Mikrobiologie und Virologie, Uniklinikum Dresden, Dresden, Germany; InfectoGnostics Research Campus, Jena, Germany
| | - G I Brennan
- National MRSA Reference Laboratory, St. James's Hospital, Dublin, Ireland
| | - B O'Connell
- Department of Clinical Microbiology, St. James's Hospital, Dublin, Ireland
| | - A Blomfeldt
- Department of Microbiology and Infection Control, Akershus University Hospital, Lørenskog, Norway
| | - B A McManus
- Microbiology Research Unit, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland
| | - W Schneider-Brachert
- Department of Infection Prevention and Infectious Diseases, University Hospital Regensburg, Regensburg, Germany
| | - J Tkadlec
- Department of Medical Microbiology, Charles University, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic
| | - R Ehricht
- Leibniz Institute of Photonic Technology (IPHT), Jena, Germany; InfectoGnostics Research Campus, Jena, Germany; Institute of Physical Chemistry, Friedrich-Schiller University, Jena, Germany
| | - A Senok
- College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, United Arab Emirates
| | - M D Bartels
- Department of Clinical Microbiology, Amager and Hvidovre Hospital, Hvidovre, Denmark; Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - D C Coleman
- Microbiology Research Unit, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland.
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Finsterwalder SK, Loncaric I, Cabal A, Szostak MP, Barf LM, Marz M, Allerberger F, Burgener IA, Tichy A, Feßler AT, Schwarz S, Monecke S, Ehricht R, Ruppitsch W, Spergser J, Künzel F. Dogs as carriers of virulent and resistant genotypes of Clostridioides difficile. Zoonoses Public Health 2022; 69:673-681. [PMID: 35546073 PMCID: PMC9544694 DOI: 10.1111/zph.12956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 04/19/2022] [Accepted: 04/25/2022] [Indexed: 11/29/2022]
Abstract
While previous research on zoonotic transmission of community-acquired Clostridioides difficile infection (CA-CDI) focused on food-producing animals, the present study aimed to investigate whether dogs are carriers of resistant and/or virulent C. difficile strains. Rectal swabs were collected from 323 dogs and 38 C. difficile isolates (11.8%) were obtained. Isolates were characterized by antimicrobial susceptibility testing, whole-genome sequencing (WGS) and a DNA hybridization assay. Multilocus sequence typing (MLST), core genome MLST (cgMLST) and screening for virulence and antimicrobial resistance genes were performed based on WGS. Minimum inhibitory concentrations for erythromycin, clindamycin, tetracycline, vancomycin and metronidazole were determined by E-test. Out of 38 C. difficile isolates, 28 (73.7%) carried genes for toxins. The majority of isolates belonged to MLST sequence types (STs) of clade I and one to clade V. Several isolates belonged to STs previously associated with human CA-CDI. However, cgMLST showed low genetic relatedness between the isolates of this study and C. difficile strains isolated from humans in Austria for which genome sequences were publicly available. Four isolates (10.5%) displayed resistance to three of the tested antimicrobial agents. Isolates exhibited resistance to erythromycin, clindamycin, tetracycline and metronidazole. These phenotypic resistances were supported by the presence of the resistance genes erm(B), cfr(C) and tet(M). All isolates were susceptible to vancomycin. Our results indicate that dogs may carry virulent and antimicrobial-resistant C. difficile strains.
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Affiliation(s)
- S K Finsterwalder
- Institute of Microbiology, University of Veterinary Medicine Vienna, Vienna, Austria.,Clinical Unit of Internal Medicine Small Animals, University of Veterinary Medicine Vienna, Vienna, Austria
| | - I Loncaric
- Institute of Microbiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - A Cabal
- AGES - Austrian Agency for Health and Food Safety, Vienna, Austria
| | - M P Szostak
- Institute of Microbiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - L M Barf
- Faculty of Mathematics and Computer Science, Friedrich Schiller University Jena, Jena, Germany.,Max Planck Institute for Science of Human History, Jena, Germany
| | - M Marz
- Faculty of Mathematics and Computer Science, Friedrich Schiller University Jena, Jena, Germany.,FLI Leibniz Institute for Age Research, Jena, Germany.,InfectoGnostics Research Campus Jena, Jena, Germany
| | - F Allerberger
- AGES - Austrian Agency for Health and Food Safety, Vienna, Austria
| | - I A Burgener
- Clinical Unit of Internal Medicine Small Animals, University of Veterinary Medicine Vienna, Vienna, Austria
| | - A Tichy
- Department of Biomedical Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - A T Feßler
- Department of Veterinary Medicine, Centre of Infection Medicine, Institute of Microbiology and Epizootics, Freie Universität Berlin, Berlin, Germany.,Department of Veterinary Medicine, Veterinary Centre for Resistance Research (TZR), Freie Universität Berlin, Berlin, Germany
| | - S Schwarz
- Department of Veterinary Medicine, Centre of Infection Medicine, Institute of Microbiology and Epizootics, Freie Universität Berlin, Berlin, Germany.,Department of Veterinary Medicine, Veterinary Centre for Resistance Research (TZR), Freie Universität Berlin, Berlin, Germany
| | - S Monecke
- InfectoGnostics Research Campus Jena, Jena, Germany.,Leibniz Institute of Photonic Technology (IPHT), Jena, Germany.,Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinik Dresden, Dresden, Germany
| | - R Ehricht
- InfectoGnostics Research Campus Jena, Jena, Germany.,Leibniz Institute of Photonic Technology (IPHT), Jena, Germany.,Institute of Physical Chemistry, Friedrich Schiller University Jena, Jena, Germany
| | - W Ruppitsch
- AGES - Austrian Agency for Health and Food Safety, Vienna, Austria
| | - J Spergser
- Institute of Microbiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - F Künzel
- Clinical Unit of Internal Medicine Small Animals, University of Veterinary Medicine Vienna, Vienna, Austria
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4
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Schauer B, Szostak MP, Ehricht R, Monecke S, Feßler AT, Schwarz S, Spergser J, Krametter-Frötscher R, Loncaric I. Diversity of methicillin-resistant coagulase-negative Staphylococcus spp. and methicillin-resistant Mammaliicoccus spp. isolated from ruminants and New World camelids. Vet Microbiol 2021; 254:109005. [PMID: 33582485 DOI: 10.1016/j.vetmic.2021.109005] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 01/29/2021] [Indexed: 11/18/2022]
Abstract
Information about livestock carrying methicillin-resistant coagulase-negative staphylococci and mammaliicocci (MRCoNS/MRM) is scarce. The study was designed to gain knowledge of the prevalence, the phenotypic and genotypic antimicrobial resistance and the genetic diversity of MRCoNS/MRM originating from ruminants and New World camelids. In addition, a multi-locus sequence typing scheme for the characterization of Mammaliicoccus (formerly Staphylococcus) sciuri was developed. The study was conducted from April 2014 to January 2017 at the University Clinic for Ruminants and the Institute of Microbiology at the University of Veterinary Medicine Vienna. Seven hundred twenty-three nasal swabs originating from ruminants and New World camelids with and without clinical signs were examined. After isolation, MRCoNS/MRM were identified by MALDI-TOF, rpoB sequencing and typed by DNA microarray-based analysis and PCR. Antimicrobial susceptibility testing was conducted by agar disk diffusion. From all 723 nasal swabs, 189 MRCoNS/MRM were obtained. Members of the Mammaliicoccus (M.) sciuri group were predominant (M. sciuri (n = 130), followed by M. lentus (n = 43), M. fleurettii (n = 11)). In total, 158 out of 189 isolates showed phenotypically a multi-resistance profile. A seven-loci multi-locus sequence typing scheme for M. sciuri was developed. The scheme includes the analysis of internal segments of the house-keeping genes ack, aroE, ftsZ, glpK, gmk, pta1 and tpiA. In total, 28 different sequence types (STs) were identified among 92 selected M. sciuri isolates. ST1 was the most prevalent ST (n = 35), followed by ST 2 (n = 15), ST3 and ST5 (each n = 5), ST4 (n = 3), ST6, ST7, ST8, ST9, ST10 and ST11 (each n = 2).
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Affiliation(s)
- B Schauer
- University Clinic for Ruminants, University of Veterinary Medicine, 1210, Vienna, Austria; Institute of Microbiology, University of Veterinary Medicine, 1210, Vienna, Austria
| | - M P Szostak
- Institute of Microbiology, University of Veterinary Medicine, 1210, Vienna, Austria
| | - R Ehricht
- Leibniz Institute of Photonic Technology (IPHT), 07743, Jena, Germany; InfectoGnostics Research Campus, Philosophenweg 7, 07749, Jena, Germany; Friedrich Schiller University Jena, Institute of Physical Chemistry, 07743, Jena, Germany
| | - S Monecke
- Leibniz Institute of Photonic Technology (IPHT), 07743, Jena, Germany; InfectoGnostics Research Campus, Philosophenweg 7, 07749, Jena, Germany; Institute for Medical Microbiology and Hygiene, Technical University of Dresden, 01307, Dresden, Germany
| | - A T Feßler
- Institute of Microbiology and Epizootics, Centre for Infection Medicine, Department of Veterinary Medicine, Freie Universität Berlin, 14163, Berlin, Germany
| | - S Schwarz
- Institute of Microbiology and Epizootics, Centre for Infection Medicine, Department of Veterinary Medicine, Freie Universität Berlin, 14163, Berlin, Germany
| | - J Spergser
- Institute of Microbiology, University of Veterinary Medicine, 1210, Vienna, Austria
| | - R Krametter-Frötscher
- University Clinic for Ruminants, University of Veterinary Medicine, 1210, Vienna, Austria
| | - I Loncaric
- Institute of Microbiology, University of Veterinary Medicine, 1210, Vienna, Austria.
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5
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McManus BA, Aloba BK, Earls MR, Brennan GI, O'Connell B, Monecke S, Ehricht R, Shore AC, Coleman DC. Multiple distinct outbreaks of Panton-Valentine leucocidin-positive community-associated meticillin-resistant Staphylococcus aureus in Ireland investigated by whole-genome sequencing. J Hosp Infect 2020; 108:72-80. [PMID: 33259881 DOI: 10.1016/j.jhin.2020.11.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 11/20/2020] [Accepted: 11/24/2020] [Indexed: 01/17/2023]
Abstract
BACKGROUND Panton-Valentine leucocidin (PVL)-positive community-associated meticillin-resistant Staphylococcus aureus (CA-MRSA) is increasingly associated with infection outbreaks. AIM To investigate multiple suspected PVL-positive CA-MRSA outbreaks using whole-genome sequencing (WGS). METHODS Forty-six suspected outbreak-associated isolates from 36 individuals at three separate Irish hospitals (H1-H3) and from separate incidents involving separate families associated with H2 were investigated by whole-genome multi-locus sequence typing (wgMLST). FINDINGS Two clusters (CH1 and CH2) consisting of 8/10 and 6/6 PVL-positive t008 ST8-MRSA-IVa isolates from H1 and H2, respectively, were identified. Within each cluster, neighbouring isolates were separated by ≤5 allelic differences; however, ≥73 allelic differences were identified between the clusters, indicating two independent outbreaks. Isolates from the H3 maternity unit formed two clusters (CH3-SCI and CH3-SCII) composed of four PVL-negative t4667 ST5-MRSA-V and 14 PVL-positive t002 ST5-MRSA-IVc isolates, respectively. Within clusters, neighbouring isolates were separated by ≤24 allelic differences, whereas both clusters were separated by 1822 allelic differences, indicating two distinct H3 outbreaks. Eight PVL-positive t127 ST1-MRSA-V+fus and three PVL-negative t267 ST97-MRSA-V+fus isolates from two distinct H2-associated families FC1 (N = 4) and FC2 (N = 7) formed three separate clusters (FC1 (t127), FC2 (t127) and FC2 (t267)). Neighbouring isolates within clusters were closely related and exhibited ≤7 allelic differences. Intrafamilial transmission was apparent, but the detection of ≥48 allelic differences between clusters indicated no interfamilial transmission. CONCLUSION The frequent importation of PVL-positive CA-MRSA into healthcare settings, transmission and association with outbreaks is a serious ongoing concern. WGS is a highly discriminatory, informative method for deciphering such outbreaks conclusively.
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Affiliation(s)
- B A McManus
- Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland
| | - B K Aloba
- Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland
| | - M R Earls
- Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland
| | - G I Brennan
- National MRSA Reference Laboratory, St James's Hospital, Dublin, Ireland
| | - B O'Connell
- National MRSA Reference Laboratory, St James's Hospital, Dublin, Ireland
| | - S Monecke
- Leibniz Institute of Photonic Technology (IPHT), Jena, Germany; InfectoGnostics Research Campus Jena e. V., Jena, Germany; Institut fuer Medizinische Mikrobiologie und Hygiene, Medizinische Fakultaet 'Carl Gustav Carus', Dresden, Germany
| | - R Ehricht
- Leibniz Institute of Photonic Technology (IPHT), Jena, Germany; InfectoGnostics Research Campus Jena e. V., Jena, Germany; Friedrich-Schiller University, Institute of Physical Chemistry, Jena, Germany
| | - A C Shore
- Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland
| | - D C Coleman
- Microbiology Research Unit, Division of Oral Biosciences, Dublin Dental University Hospital, University of Dublin, Trinity College Dublin, Dublin, Ireland.
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Senok A, Nassar R, Kaklamanos E, Belhoul K, Fanas SA, Nassar M, Azar A, Müller E, Reissig A, Gawlik D, Monecke S, Ehricht R. Genotyping Staphylococcus aureus isolates associated with nasal colonization and environmental contamination in academic dental clinics. J Infect Public Health 2020. [DOI: 10.1016/j.jiph.2020.01.135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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7
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Senok A, Somily A, Nassar R, Garaween G, Sing GK, Müller E, Reissig A, Gawlik D, Ehricht R, Monecke S. Emergence of novel methicillin resistant Staphylococcus aureus strains in a tertiary care facility in Riyadh, Saudi Arabia. J Infect Public Health 2020. [DOI: 10.1016/j.jiph.2020.01.047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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8
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Thunberg U, Hugosson S, Fredlund H, Cao Y, Ehricht R, Monecke S, Muller E, Engelmann S, Soderquist B. Anti-Staphylococcal humoral immune response in patients with chronic rhinosinusitis. RHINOL 2019. [DOI: 10.4193/rhinol/19.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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9
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Olofsson M, Matussek A, Ehricht R, Lindgren PE, Östgren CJ. Differences in molecular epidemiology of Staphylococcus aureus and Escherichia coli in nursing home residents and people in unassisted living situations. J Hosp Infect 2018; 101:76-83. [PMID: 30237119 DOI: 10.1016/j.jhin.2018.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 09/10/2018] [Indexed: 01/28/2023]
Abstract
BACKGROUND The usefulness of colonization pressure as a working model and proxy for infection transmission is limited due to the inability to grade or quantify the specific risk within environments that are subject to change. AIM To elaborate on the colonization pressure model by comparing the molecular epidemiology of two bacteria, Staphylococcus aureus and Escherichia coli, among residents in a nursing home and people in unassisted living situations. METHODS A cross-sectional study of 73 elderly residents from a village in south-central Sweden was conducted. Of these, 35 were residents of a nursing home, and 34 lived in an own place of residence in the same geographical area. Samples of two representative bacterial species were collected from multiple body sites and analysed for molecular diversity. FINDINGS Combining all body sites, 47% of the participants were colonized with S. aureus and 93% with E. coli. The nursing home group, the group in unassisted living situations, and both units combined, held 16, 17, and 29 different S. aureus spa types, respectively. The corresponding numbers of different E. coli serogenotypes were 34, 28, and 48. Diabetes mellitus was associated with more frequent colonization with S. aureus. CONCLUSION The molecular diversity of bacteria found within different forms of accommodation was within the same range. Hospital quality hygiene might have contributed to the absence of homogenization of the molecular diversity within the nursing home group. Diabetes mellitus might have played a role in a patient selection characterized by advanced age.
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Affiliation(s)
- M Olofsson
- Ödeshög Health Care Centre, Ödeshög, Sweden; Division of Community Medicine, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.
| | - A Matussek
- Department of Laboratory Medicine, Region Jönköping County, Sweden; Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institute, Stockholm, Sweden; Karolinska University Laboratory, Stockholm, Sweden
| | - R Ehricht
- Abbott (Alere Technologies GmbH), Jena, Germany; InfectoGnostics Research Campus, Jena, Germany; Leibniz Institute of Photonic Technology, Jena, Germany
| | - P-E Lindgren
- Department of Laboratory Medicine, Region Jönköping County, Sweden; Division of Medical Microbiology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - C J Östgren
- Ödeshög Health Care Centre, Ödeshög, Sweden; Division of Community Medicine, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
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10
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Schauer B, Krametter-Frötscher R, Knauer F, Ehricht R, Monecke S, Feßler A, Schwarz S, Grunert T, Spergser J, Loncaric I. Diversity of methicillin-resistant Staphylococcus aureus (MRSA) isolated from Austrian ruminants and New World camelids. Vet Microbiol 2018; 215:77-82. [DOI: 10.1016/j.vetmic.2018.01.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 01/14/2018] [Accepted: 01/15/2018] [Indexed: 11/30/2022]
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11
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Senok A, Ehricht R, Monecke S, Al-Saedan R, Somily A. Molecular characterization of methicillin-resistant Staphylococcus aureus in nosocomial infections in a tertiary-care facility: emergence of new clonal complexes in Saudi Arabia. New Microbes New Infect 2016; 14:13-8. [PMID: 27621823 PMCID: PMC5009225 DOI: 10.1016/j.nmni.2016.07.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 07/13/2016] [Accepted: 07/25/2016] [Indexed: 12/13/2022] Open
Abstract
Changes in the molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) continue to be reported. This study was carried out to characterize MRSA isolates in Saudi Arabia. MRSA isolates causing nosocomial infections (n = 117) obtained from 2009–2015 at a tertiary-care facility in Riyadh, Saudi Arabia, were studied. Molecular characterization of isolates was carried out using the StaphyType DNA microarray (Alere Technologies, Jena, Germany). Fourteen clonal complexes (CC) were identified, with the most common being CC80 (n = 35), CC6 (n = 15), CC5 (n = 13) and CC22 (n = 12). With the exception of nine ST239 MRSA-III isolates, all others were of community-associated MRSA lineages. The following strains are identified for the first time in Saudi Arabia: ST8-MRSA-IV [PVL+/ACME+], USA300 (n = 1); ST72-MRSA-IV USA700 (n = 1); CC5-MRSA-IV, [PVL+/edinA+], WA MRSA-121 (n = 1); CC5-MRSA-V+SCCfus, WA MRSA-14/109 (n = 2), CC97-MRSA-IV, WA MRSA-54/63; CC2250/2277-MRSA-IV and WA MRSA-114. CC15-MRSA (n = 3) was identified for the first time in clinical infection in Saudi Arabia. None of the isolates harboured vancomycin resistance genes, while genes for resistance to mupirocin and quaternary ammonium compounds were found in one and nine isolates respectively. Fifty-seven isolates (48.7%) were positive for Panton-Valentine leukocidin genes. While the staphylokinase (sak) and staphylococcal complement inhibitor (scn) genes were present in over 95% of the isolates, only 37.6% had the chemotaxis-inhibiting protein (chp) gene. Increasing occurrence of community-acquired MRSA lineages plus emergence of pandemic and rare MRSA strains is occurring in our setting. Strict infection control practices are important to limit the dissemination of these MRSA strains.
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Affiliation(s)
- A. Senok
- Department of Microbiology and Immunology, College of Medicine, Alfaisal University, Saudi Arabia
- Corresponding author: A. Senok, Department of Microbiology & Immunology, College of Medicine, Alfaisal University, PO Box 50927, Riyadh 11533, Saudi ArabiaDepartment of Microbiology & ImmunologyCollege of MedicineAlfaisal UniversityPO Box 50927Riyadh11533Saudi Arabia
| | - R. Ehricht
- Alere Technologies GmbH, Germany
- InfectoGnostics Research Campus, Jena, Germany
| | - S. Monecke
- Alere Technologies GmbH, Germany
- InfectoGnostics Research Campus, Jena, Germany
- Institute for Medical Microbiology and Hygiene, Technische Universität Dresden, Dresden, Germany
| | - R. Al-Saedan
- Department of Clinical Laboratory Sciences, College of Applied Medical Science, King Saud University, Saudi Arabia
| | - A. Somily
- Department of Pathology and Laboratory Medicine, College of Medicine, King Khalid University Hospital and King Saud University, Riyadh, Saudi Arabia
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Madzgalla S, Syed MA, Khan MA, Rehman SS, Müller E, Reissig A, Ehricht R, Monecke S. Molecular characterization of Staphylococcus aureus isolates causing skin and soft tissue infections in patients from Malakand, Pakistan. Eur J Clin Microbiol Infect Dis 2016; 35:1541-7. [PMID: 27262852 DOI: 10.1007/s10096-016-2695-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 05/24/2016] [Indexed: 11/24/2022]
Abstract
Comparatively few studies have been published describing Staphylococcus aureus/MRSA epidemiology in Central Asia including Pakistan. Here, we report the genotyping of Staphylococcus aureus strains (that include both methicillin-susceptible and methicillin-resistant Staphylococcus aureus) from community- and hospital-acquired skin and soft-tissue infections in a tertiary care hospital in the Malakand district of the Khyber Pakhtunkhwa Province of Pakistan. Forty-five isolates of Staphylococcus aureus were characterized by microarray hybridization. Twenty isolates (44 %) were MRSA, whereas 22 (49 %) were PVL-positive. Fourteen isolates (31 %) harboured both mecA and PVL genes. The dominant clones were CC121-MSSA (n = 15, 33 %) and the PVL-positive "Bengal Bay Clone" (ST772-MRSA-V; n = 13, 29 %). The PVL-positive CC8-MRSA-IV strain "USA300" was found once. The pandemic ST239-MRSA-III strain was absent, although it has previously been observed in Pakistan. These observations require a re-assessment of schemes for initial antibiotic therapy to cover MRSA and they emphasise the need for a rapid and non-molecular test for PVL.
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Affiliation(s)
- S Madzgalla
- Alere Technologies GmbH, Jena, Germany.,InfectoGnostics Research Campus, Jena, Germany
| | - M A Syed
- Infectious Diseases Research Group, Department of Microbiology, University of Haripur, Haripur, Pakistan
| | - M A Khan
- Infectious Diseases Research Group, Department of Microbiology, University of Haripur, Haripur, Pakistan
| | - S S Rehman
- Infectious Diseases Research Group, Department of Microbiology, University of Haripur, Haripur, Pakistan
| | - E Müller
- Alere Technologies GmbH, Jena, Germany.,InfectoGnostics Research Campus, Jena, Germany
| | - A Reissig
- Alere Technologies GmbH, Jena, Germany.,InfectoGnostics Research Campus, Jena, Germany
| | - R Ehricht
- Alere Technologies GmbH, Jena, Germany.,InfectoGnostics Research Campus, Jena, Germany
| | - S Monecke
- Alere Technologies GmbH, Jena, Germany. .,Institute for Medical Microbiology and Hygiene, Technische Universität Dresden, Dresden, Germany. .,InfectoGnostics Research Campus, Jena, Germany.
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Bar-Gal GK, Blum S, Hadas L, Ehricht R, Monecke S, Leitner G. Host-specificity of Staphylococcus aureus causing intramammary infections in dairy animals assessed by genotyping and virulence genes. Vet Microbiol 2015; 176:143-54. [DOI: 10.1016/j.vetmic.2015.01.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 12/31/2014] [Accepted: 01/07/2015] [Indexed: 02/04/2023]
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Nimmo GR, Steen JA, Monecke S, Ehricht R, Slickers P, Thomas JC, Appleton S, Goering RV, Robinson DA, Coombs GW. ST2249-MRSA-III: a second major recombinant methicillin-resistant Staphylococcus aureus clone causing healthcare infection in the 1970s. Clin Microbiol Infect 2015; 21:444-50. [PMID: 25708549 DOI: 10.1016/j.cmi.2014.12.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 12/04/2014] [Accepted: 12/19/2014] [Indexed: 11/24/2022]
Abstract
Typing of healthcare-associated methicillin-resistant Staphylococcus aureus (MRSA) from Australia in the 1970s revealed a novel clone, ST2249-MRSA-III (CC45), present from 1973 to 1979. This clone was present before the Australian epidemic caused by the recombinant clone, ST239-MRSA-III. This study aimed to characterize the genome of ST2249-MRSA-III to establish its relationship to other MRSA clones. DNA microarray analysis was conducted and a draft genome sequence of ST2249 was obtained. The recombinant structure of the ST2249 genome was revealed by comparisons to publicly available ST239 and ST45 genomes. Microarray analysis of genomic DNA of 13 ST2249 isolates showed gross similarities with the ST239 chromosome in a segment around the origin of replication and with ST45 for the remainder of the chromosome. Recombination breakpoints were precisely determined by the changing pattern of nucleotide polymorphisms in the genome sequence of ST2249 isolate SK1585 compared with ST239 and ST45. One breakpoint was identified to the right of oriC, between sites 1014 and 1065 of the gene D484_00045. Another was identified to the left of oriC, between sites 1185 and 1248 of D484_01632. These results indicate that ST2249 inherited approximately 35.3% of its chromosome from an ST239-like parent and 64.7% from an ST45-like parent. ST2249-MRSA-III resulted from a major recombination between parents that resemble ST239 and ST45. Although only limited Australian archival material is available, the oldest extant isolate of ST2249 predates the oldest Australian isolate of ST239 by 3 years. It is therefore plausible that these two recombinant clones were introduced into Australia separately.
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Affiliation(s)
- G R Nimmo
- Pathology Queensland Central Laboratory, Brisbane, Qld, Australia; Griffith University School of Medicine, Gold Coast, Qld, Australia.
| | - J A Steen
- Queensland Centre for Medical Genomics, University of Queensland, Qld, Australia
| | - S Monecke
- Alere Technologies GmbH, Jena, Germany; Institute for Medical Microbiology and Hygiene, Technische Universitat Dresden, Dresden, Germany
| | - R Ehricht
- Alere Technologies GmbH, Jena, Germany
| | | | - J C Thomas
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS, USA; Department of Biology, University of Bolton, Bolton, United Kingdom
| | - S Appleton
- Queensland Medical Laboratory, Murrarie, Qld, Australia
| | | | - D A Robinson
- Department of Microbiology, University of Mississippi Medical Center, Jackson, MS, USA
| | - G W Coombs
- Australian Collaborating Centre for Enterococcus and Staphylococcus Species (ACCESS) Typing and Research, Curtin University, Perth, WA, Australia; Pathwest Laboratory Medicine-WA, Royal Perth Hospital, Perth, WA, Australia
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Wendlandt S, Li J, Ho J, Porta MA, Fessler AT, Wang Y, Kadlec K, Monecke S, Ehricht R, Boost M, Schwarz S. Enterococcal multiresistance gene cluster in methicillin-resistant Staphylococcus aureus from various origins and geographical locations. J Antimicrob Chemother 2014; 69:2573-5. [DOI: 10.1093/jac/dku137] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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16
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Schlotter K, Huber-Schlenstedt R, Gangl A, Hotzel H, Monecke S, Müller E, Reißig A, Proft S, Ehricht R. Multiple cases of methicillin-resistant CC130 Staphylococcus aureus harboring mecC in milk and swab samples from a Bavarian dairy herd. J Dairy Sci 2014; 97:2782-8. [PMID: 24630668 DOI: 10.3168/jds.2013-7378] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 02/04/2014] [Indexed: 11/19/2022]
Abstract
The discovery of a new mecA homolog, mecC, necessitates a modification of diagnostic procedures for the identification of methicillin-resistant Staphylococcus aureus (MRSA), as most assays used for the genotypic and phenotypic mecA detection cannot currently recognize mecC. Although the prevalence, distribution, and importance of mecC are not yet completely understood, an exchange of mecC-MRSA between humans and animals seems possible. All previously reported observations of mecC-positive strains have been sporadic. To the best of our knowledge, this is the first report about multiple cases of mecC-positive Staph. aureus in 1 dairy herd. Clonal complex 130 Staph. aureus harboring mecC were found in milk samples from 16 of 56 lactating cows kept in a herd in Bavaria, Germany. Almost all quarter milk samples positive for mecC-MRSA had the lowest possible California Mastitis Test score; composite somatic cell counts obtained from monthly milk recordings showed a mean of 51,600 cells/mL in mecC-MRSA affected cows. Additionally, mecC-positive clonal complex 130 Staph. aureus were detected in swab samples from the mammary skin and a teat lesion of 1 cow from this herd. This report suggests that mecC-carrying strains are able to spread among livestock, and that they have the ability to cause multiple cases in single herds. Therefore, future studies targeting MRSA in dairy cows need to consider mecC.
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Affiliation(s)
- K Schlotter
- Tiergesundheitsdienst Bayern e.V. (Bavarian Animal Health Service), Senator-Gerauer-Straße 23, 85586 Poing, Germany.
| | - R Huber-Schlenstedt
- Tiergesundheitsdienst Bayern e.V. (Bavarian Animal Health Service), Senator-Gerauer-Straße 23, 85586 Poing, Germany
| | - A Gangl
- Tiergesundheitsdienst Bayern e.V. (Bavarian Animal Health Service), Senator-Gerauer-Straße 23, 85586 Poing, Germany
| | - H Hotzel
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Bacterial Infections and Zoonoses, Naumburger Str. 96a, 07743 Jena, Germany
| | - S Monecke
- Institute for Medical Microbiology and Hygiene, Technical University of Dresden, Fiedlerstr. 42, 01307 Dresden, Germany; Alere Technologies GmbH, Loebstedter Str. 103-105, 07749 Jena, Germany
| | - E Müller
- Alere Technologies GmbH, Loebstedter Str. 103-105, 07749 Jena, Germany
| | - A Reißig
- Alere Technologies GmbH, Loebstedter Str. 103-105, 07749 Jena, Germany
| | - S Proft
- Alere Technologies GmbH, Loebstedter Str. 103-105, 07749 Jena, Germany
| | - R Ehricht
- Alere Technologies GmbH, Loebstedter Str. 103-105, 07749 Jena, Germany
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Fessler AT, Calvo N, Gutierrez N, Munoz Bellido JL, Fajardo M, Garduno E, Monecke S, Ehricht R, Kadlec K, Schwarz S. Cfr-mediated linezolid resistance in methicillin-resistant Staphylococcus aureus and Staphylococcus haemolyticus associated with clinical infections in humans: two case reports. J Antimicrob Chemother 2013; 69:268-70. [DOI: 10.1093/jac/dkt331] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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18
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Wendlandt S, Kadlec K, Fessler AT, Monecke S, Ehricht R, van de Giessen AW, Hengeveld PD, Huijsdens X, Schwarz S, van Duijkeren E. Resistance phenotypes and genotypes of methicillin-resistant Staphylococcus aureus isolates from broiler chickens at slaughter and abattoir workers. J Antimicrob Chemother 2013; 68:2458-63. [DOI: 10.1093/jac/dkt239] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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19
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Herrmann B, Christerson L, Ruettger A, Gravningen K, Ehricht R, Sachse K. O4-S1.01 Rapid array-based multilocus genotyping of Chlamydia trachomatis: the easy and economical alternative. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050109.139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Luedicke C, Slickers P, Ehricht R, Monecke S. Molecular fingerprinting of Staphylococcus aureus from bone and joint infections. Eur J Clin Microbiol Infect Dis 2010; 29:457-63. [PMID: 20186451 DOI: 10.1007/s10096-010-0884-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2009] [Accepted: 01/31/2010] [Indexed: 11/25/2022]
Abstract
The objective of the study was to determine if a clonal complex (CC) of Staphylococcus aureus or certain virulence and adhesion factors were associated with infections of bones and prosthetic implants. One hundred and nineteen isolates were characterised using microarrays. There was no evidence for a single virulence factor or CC being causative for bone and implant infections. Isolates belonged to 20 different CCs, with CC8 (19.33%), CC45 (17.65%) and CC30 (12.61%) being dominant. Population structure and the relative abundances of virulence genes was similar to previously described isolates from healthy carriers. Differences to carrier isolates included a higher proportion of CC45, a lower proportion of CC15, as well as a higher abundance of sak (staphylokinase) among patient isolates. For 23 patients with infections of total knee or hip prosthetics, it was possible to simultaneously obtain nasal swabs. Fifteen (65.2%) carried S. aureus in their anterior nares. In nine of them (39.1%), isolates from the infection site were identical to carriage isolates. This suggests an elevated risk of infection for S. aureus carriers and the possibility of endogenous infection in a high proportion of them. Therefore, the pre-operative screening and eradication of S. aureus in patients receiving total joint prosthetics should be considered.
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Affiliation(s)
- C Luedicke
- Medical Clinic and Policlinic I, University Hospital Dresden, Dresden, Germany
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21
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Fessler A, Scott C, Kadlec K, Ehricht R, Monecke S, Schwarz S. Characterization of methicillin-resistant Staphylococcus aureus ST398 from cases of bovine mastitis. J Antimicrob Chemother 2010; 65:619-25. [DOI: 10.1093/jac/dkq021] [Citation(s) in RCA: 215] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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22
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Scicluna EA, Shore AC, Thürmer A, Ehricht R, Slickers P, Borg MA, Coleman DC, Monecke S. Characterisation of MRSA from Malta and the description of a Maltese epidemic MRSA strain. Eur J Clin Microbiol Infect Dis 2009; 29:163-70. [PMID: 19911206 DOI: 10.1007/s10096-009-0834-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Accepted: 10/17/2009] [Indexed: 01/09/2023]
Abstract
Malta has one of the highest prevalence rates of methicillin-resistant Staphylococcus aureus (MRSA) in Europe. However, only limited typing data are currently available. In order to address this situation, 45 MRSA isolates from the Mater Dei Hospital in Msida, Malta, were characterised using DNA microarrays. The most common strain was ST22-MRSA-IV (UK-EMRSA-15, 30 isolates). Sporadic strains included ST36-MRSA-II (UK-EMRSA-16, two isolates), PVL-positive ST80-MRSA-IV (European Clone, one isolate), ST228-MRSA-I (Italian Clone/South German Epidemic Strain, one isolate) and ST239-MRSA-III (Vienna/Hungarian/Brazilian Epidemic Strain, one isolate). Ten MRSA isolates belonged to a clonal complex (CC) 5/ST149, spa type t002 strain. This strain harboured an SCCmec IV element (mecA, delta mecR, ugpQ, dcs, ccrA2 and ccrB2), as well as novel alleles of ccrA/B and the fusidic acid resistance element Q6GD50 (previously described in the sequenced strain MSSA476, BX571857.1:SAS0043). It also carried the gene for enterotoxin A (sea) and the egc enterotoxin locus, as well as (in nine out of ten isolates) genes encoding the toxic shock syndrome toxin (tst1) and enterotoxins C and L (sec, sel). While the presence of the other MRSA strains suggests foreign importation due to travel between Malta and other European countries, the CC5/t002 strain appears, so far, to be restricted to Malta.
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Affiliation(s)
- E A Scicluna
- Infection Control Unit, Mater Dei Hospital, Msida, Malta
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Kadlec K, Ehricht R, Monecke S, Steinacker U, Kaspar H, Mankertz J, Schwarz S. Diversity of antimicrobial resistance pheno- and genotypes of methicillin-resistant Staphylococcus aureus ST398 from diseased swine. J Antimicrob Chemother 2009; 64:1156-64. [DOI: 10.1093/jac/dkp350] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Monecke S, Ehricht R, Slickers P, Wiese N, Jonas D. Intra-strain variability of methicillin-resistant Staphylococcus aureus strains ST228-MRSA-I and ST5-MRSA-II. Eur J Clin Microbiol Infect Dis 2009; 28:1383-90. [DOI: 10.1007/s10096-009-0796-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Accepted: 07/24/2009] [Indexed: 11/28/2022]
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25
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Monecke S, Ehricht R, Slickers P, Tan HL, Coombs G. The molecular epidemiology and evolution of the Panton–Valentine leukocidin-positive, methicillin-resistant Staphylococcus aureus strain USA300 in Western Australia. Clin Microbiol Infect 2009; 15:770-6. [DOI: 10.1111/j.1469-0691.2009.02792.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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26
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Felder KM, Hoelzle K, Wittenbrink MM, Zeder M, Ehricht R, Hoelzle LE. A DNA microarray facilitates the diagnosis of Bacillus anthracis in environmental samples. Lett Appl Microbiol 2009; 49:324-31. [PMID: 19552771 DOI: 10.1111/j.1472-765x.2009.02664.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIMS In order to improve the diagnosis of Bacillus anthracis in environmental samples, we established a DNA microarray based on the ArrayTube technology of Clondiag. METHODS AND RESULTS Total DNA of a bacterial colony is randomly biotinylated and hybridized to the array. The probes on the array target the virulence genes, the genomic marker gene rpoB, as well as the selective 16S rDNA sequence regions of B. anthracis, of the Bacillus cereus group and of Bacillus subtilis. Eight B. anthracis reference strains were tested and correctly identified. Among the analysed environmental Bacillus isolates, no virulent B. anthracis strain was detected. CONCLUSIONS This array clearly differentiates B. anthracis from members of the B. cereus group and other Bacillus species in environmental samples by chromosomal (rpoB) and plasmid markers. Additionally, recognition of B. cereus strains harbouring the toxin genes or atypical B. anthracis strains that have lost the virulence plasmids is feasible. SIGNIFICANCE AND IMPACT OF THE STUDY The array is applicable to the complex diagnostics for B. anthracis detection in environmental samples. Because of low costs, high security and easy handling, the microarray is applicable to routine diagnostics.
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Affiliation(s)
- K M Felder
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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27
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Monecke S, Luedicke C, Slickers P, Ehricht R. Molecular epidemiology of Staphylococcus aureus in asymptomatic carriers. Eur J Clin Microbiol Infect Dis 2009; 28:1159-65. [DOI: 10.1007/s10096-009-0752-2] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2009] [Accepted: 04/22/2009] [Indexed: 11/25/2022]
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28
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Monecke S, Jatzwauk L, Weber S, Slickers P, Ehricht R. DNA microarray-based genotyping of methicillin-resistant Staphylococcus aureus strains from Eastern Saxony. Clin Microbiol Infect 2008; 14:534-45. [PMID: 18373691 DOI: 10.1111/j.1469-0691.2008.01986.x] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A diagnostic microarray was used to characterise a collection of methicillin-resistant Staphylococcus aureus (MRSA) isolates from hospitals in the German region of Eastern Saxony. The most abundant epidemic MRSA (EMRSA) strains were ST5-MRSA II (Rhine-Hesse EMRSA, EMRSA-3), CC5/ST228-MRSA I (South German EMRSA), ST22-MRSA IV (Barnim EMRSA, EMRSA-15) and ST45-MRSA IV (Berlin EMRSA). Other strains were found only as sporadic isolates or in minor outbreaks. These strains included ST1-MRSA IV, ST8-MRSA IV (Hannover EMRSA and others), clonal group 5 strains carrying SCCmec type IV elements (Paediatric clone), ST45-MRSA V, CC8/ST239-MRSA III and ST398-MRSA V. Panton-Valentine leukocidin-positive MRSA isolates were still very rare. The predominant strain was ST80-MRSA IV, although increasing numbers of different strains have recently been detected (ST8-MRSA IV, ST30-MRSA IV and ST59-MRSA V). For more common MRSA strains, it was possible to detect variants that differed mainly in the carriage of additional resistance determinants and certain virulence-associated genes. Detection of such variants can sometimes allow epidemic strains to be resolved beyond spa types to a hospital-specific level, which is of significant value for epidemiological purposes.
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Affiliation(s)
- S Monecke
- Institute for Medical Microbiology and Hygiene, Faculty of Medicine Carl Gustav Carus, Technical University of Dresden, Dresden, Germany.
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Monecke S, Slickers P, Ellington MJ, Kearns AM, Ehricht R. High diversity of Panton-Valentine leukocidin-positive, methicillin-susceptible isolates of Staphylococcus aureus and implications for the evolution of community-associated methicillin-resistant S. aureus. Clin Microbiol Infect 2007; 13:1157-64. [PMID: 17949441 DOI: 10.1111/j.1469-0691.2007.01833.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In total, 100 Staphylococcus aureus isolates from diverse cases of skin and soft-tissue infection at a university hospital in Saxony, Germany, were characterised using diagnostic microarrays. Virulence factors, including Panton-Valentine leukocidin (PVL), were detected and the isolates were assigned to clonal groups. Thirty isolates were positive for the genes encoding PVL. Only three PVL-positive methicillin-resistant S. aureus (MRSA) isolates were found, two of which belonged to European clone ST80-MRSA IV and one to USA300 strain ST8-MRSA IV. The remaining methicillin-susceptible PVL-positive isolates belonged to a variety of different multilocus sequence types. The predominant strains were agrI/ST22, agrII/CC5, agrIII/CC30 and agrIV/ST121. In order to check for possible bias caused by regional or local outbreak strains, an additional 18 methicillin-susceptible, PVL-positive isolates from the UK were tested. Approximately two-thirds of the UK isolates belonged to types that also comprised approximately two-thirds of the isolates from Saxony. Some methicillin-susceptible PVL-positive isolates (agrI/ST152, agrIII/ST80 and agrIII/ST96) closely resembled known epidemic community-acquired MRSA (CaMRSA) strains. These findings indicate that the current rise in PVL-positive CaMRSA could be caused by the dissemination of novel SCCmec elements among pre-existing PVL-positive strains, rather than by the spread of PVL phages among MRSA strains.
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Affiliation(s)
- S Monecke
- Institute for Medical Microbiology and Hygiene, Faculty of Medicine Carl Gustav Carus, Technical University of Dresden, Dresden, Germany.
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30
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Monecke S, Berger-Bächi B, Coombs G, Holmes A, Kay I, Kearns A, Linde HJ, O'Brien F, Slickers P, Ehricht R. Comparative genomics and DNA array-based genotyping of pandemic Staphylococcus aureus strains encoding Panton-Valentine leukocidin. Clin Microbiol Infect 2007; 13:236-49. [PMID: 17391377 DOI: 10.1111/j.1469-0691.2006.01635.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Within the last few years, methicillin-resistant Staphylococcus aureus (MRSA) strains encoding Panton-Valentine leukocidin (PVL) have emerged and spread worldwide. This epidemic can be attributed to a small number of distinct clones. The present study used a novel assay, based on multiplex linear DNA amplification and subsequent microarray hybridisation, to simultaneously detect all relevant exotoxins, antimicrobial resistance determinants and the allelic variants of agr. The genes of the staphylococcal exotoxin-like (set) locus were also included for typing purposes. This assay, together with multilocus sequence typing (MLST) and spa typing, was applied to 56 clinical isolates and reference strains representing all major pandemic PVL-MRSA lineages, as well as to phylogenetically-related strains and putative ancestors. Array hybridisation results allowed the assignment of isolates to clonal groups, which were in accordance with MLST and spa typing data. Ten distinct clonal groups of PVL-MRSA (ST1, ST5, ST8, ST22, ST30, ST59/359, ST80/583, ST88, ST93 and ST152), including 12 MLST types, were identified and analysed with regard to resistance determinants and genes coding for exotoxins. The array hybridisation data confirmed that pandemic PVL-positive strains originate from very diverse genetic backgrounds, and provided insights into the evolution of some lineages. The DNA microarray technique provides a valuable epidemiological tool for the detailed characterisation of clinical isolates and comparison of strains at a global level.
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Affiliation(s)
- S Monecke
- Institute for Medical Microbiology and Hygiene, Faculty of Medicine Carl Gustav Carus, Technical University of Dresden, Dresden, Germany.
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Monecke S, Jatzwauk L, Weber S, Ehricht R. P1304 Array-based typing of community-and healthcare associated MRSA and occurrence of epidemic strains in eastern Saxony. Int J Antimicrob Agents 2007. [DOI: 10.1016/s0924-8579(07)71144-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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32
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Monecke S, Slickers P, Hotzel H, Richter-Huhn G, Pohle M, Weber S, Witte W, Ehricht R. Microarray-based characterisation of a Panton-Valentine leukocidin-positive community-acquired strain of methicillin-resistant Staphylococcus aureus. Clin Microbiol Infect 2006; 12:718-28. [PMID: 16842566 DOI: 10.1111/j.1469-0691.2006.01420.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recent years have witnessed the emergence of novel methicillin-resistant Staphylococcus aureus (MRSA) strains that produce the potent toxin Panton-Valentine leukocidin (PVL). PVL-positive strains can cause complicated skin infections or necrotising pneumonia with high mortality, and these strains have the potential for epidemic spread in the community. In 2004-2005, two case clusters and two isolated cases were observed in eastern Saxony and southern Brandenburg. These were the first known infections with PVL-positive community-acquired MRSA (caMRSA) in this part of Germany. The isolates belonged to agr type III, spa type 44 or spa type 131, and showed a SmaI macrorestriction pattern that corresponded to caMRSA of clonal group ST80. The isolates were susceptible to levofloxacin, macrolides, clindamycin, gentamicin and vancomycin. Most isolates showed resistance to tetracycline and fusidic acid because of the presence of the tetK and far1 genes. A novel plasmid (designated pUB102) harbouring far1, tetK and blaZ was characterised and partially sequenced. Microarray analysis revealed that the caMRSA isolates harboured genes encoding several bi-component toxins (lukF/S-PVL, lukD/E, lukS/F plus hlgA, and another putative leukocidin homologue). Neither tst1 nor genes for enterotoxins A-Y were detected, but the isolates harboured several staphylococcal enterotoxin-like toxin genes (set genes), as well as genes encoding an epidermal cell differentiation inhibitor (edinB) and exfoliative toxin D (etD). Comparative analysis of other isolates from Australia, Germany, Switzerland and the UK showed that these isolates were representative of a widespread clone of caMRSA.
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Affiliation(s)
- S Monecke
- Institute for Medical Microbiology and Hygiene, Faculty of Medicine, Carl Gustav Carus at the Technical University of Dresden, Dresden, Germany.
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Schüler S, Wenz I, Wiederanders B, Slickers P, Ehricht R. An alternative method to amplify RNA without loss of signal conservation for expression analysis with a proteinase DNA microarray in the ArrayTube format. BMC Genomics 2006; 7:144. [PMID: 16768788 PMCID: PMC1526438 DOI: 10.1186/1471-2164-7-144] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2006] [Accepted: 06/12/2006] [Indexed: 11/30/2022] Open
Abstract
Background Recent developments in DNA microarray technology led to a variety of open and closed devices and systems including high and low density microarrays for high-throughput screening applications as well as microarrays of lower density for specific diagnostic purposes. Beside predefined microarrays for specific applications manufacturers offer the production of custom-designed microarrays adapted to customers' wishes. Array based assays demand complex procedures including several steps for sample preparation (RNA extraction, amplification and sample labelling), hybridization and detection, thus leading to a high variability between several approaches and resulting in the necessity of extensive standardization and normalization procedures. Results In the present work a custom designed human proteinase DNA microarray of lower density in ArrayTube® format was established. This highly economic open platform only requires standard laboratory equipment and allows the study of the molecular regulation of cell behaviour by proteinases. We established a procedure for sample preparation and hybridization and verified the array based gene expression profile by quantitative real-time PCR (QRT-PCR). Moreover, we compared the results with the well established Affymetrix microarray. By application of standard labelling procedures with e.g. Klenow fragment exo-, single primer amplification (SPA) or In Vitro Transcription (IVT) we noticed a loss of signal conservation for some genes. To overcome this problem we developed a protocol in accordance with the SPA protocol, in which we included target specific primers designed individually for each spotted oligomer. Here we present a complete array based assay in which only the specific transcripts of interest are amplified in parallel and in a linear manner. The array represents a proof of principle which can be adapted to other species as well. Conclusion As the designed protocol for amplifying mRNA starts from as little as 100 ng total RNA, it presents an alternative method for detecting even low expressed genes by microarray experiments in a highly reproducible and sensitive manner. Preservation of signal integrity is demonstrated out by QRT-PCR measurements. The little amounts of total RNA necessary for the analyses make this method applicable for investigations with limited material as in clinical samples from, for example, organ or tumour biopsies. Those are arguments in favour of the high potential of our assay compared to established procedures for amplification within the field of diagnostic expression profiling. Nevertheless, the screening character of microarray data must be mentioned, and independent methods should verify the results.
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Affiliation(s)
- Susann Schüler
- Institute of Biochemistry, Klinikum, Friedrich-Schiller-Universität Jena, Germany
| | - Ingrid Wenz
- Institute of Biochemistry, Klinikum, Friedrich-Schiller-Universität Jena, Germany
| | - B Wiederanders
- Institute of Biochemistry, Klinikum, Friedrich-Schiller-Universität Jena, Germany
| | - P Slickers
- Clondiag chip technologies GmbH Jena, Germany
| | - R Ehricht
- Clondiag chip technologies GmbH Jena, Germany
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Sachse K, Hotzel H, Slickers P, Ehricht R. The use of DNA microarray technology for detection and genetic characterisation of chlamydiae. Dev Biol (Basel) 2006; 126:203-10; discussion 326-7. [PMID: 17058496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Due to its highly parallel approach, DNA microarray technology opens up new possibilities that may be particularly beneficial for laboratory diagnosis of infectious diseases. We developed a microarray assay for detection and differentiation of all currently defined chlamydial species belonging to the genera Chlamydia and Chlamydophila using the ArrayTube system, which we found to be particularly user-friendly and economical. The test includes PCR amplification of a 23S rDNA target region with concurrent biotinylation and subsequent hybridisation in the ArrayTube, a micro-reaction tube carrying the microarray chip on the bottom. In addition to high specificity, the assay was shown to allow detection and genetic characterisation of single PCR-amplifiable target DNA copies.
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Affiliation(s)
- K Sachse
- Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Institute of Bacterial Infections and Zoonoses, Jena, Germany.
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Abstract
This study evaluated a DNA oligonucleotide array that recognised 38 different Staphylococcus aureus targets, including all relevant resistance determinants and some toxins and species-specific controls. A new method for labelling sample DNA, based on a linear multiplex amplification that incorporated biotin-labelled dUTP into the amplicon, was established, and allowed detection of hybridisation of the amplicons to the array with an enzymic precipitation reaction. The whole assay was validated by hybridisations with a panel of reference strains and cloned specific PCR products of all targets. To evaluate performance under routine conditions, the assay was used to test 100 methicillin-resistant S. aureus (MRSA) isolates collected from a university hospital in Saxony, Germany. The results showed a high correlation with conventional susceptibility data. The ermA and ermC macrolide resistance genes were found in 40% and 32% of the isolates, respectively. The most prevalent aminoglycoside resistance gene was aphA3 (57% of the isolates), followed by aacA-aphD (29%) and aadD (29%); tet genes, mupR and dfrA were rare. There were no isolates with van genes or genes involved in resistance to quinupristin-dalfopristin. Enterotoxins were detected in 27% of the isolates. Genes encoding Panton-Valentine leukocidin, toxic shock syndrome toxin and exfoliative toxins were not found. The DNA array facilitated rapid and reliable detection of resistance determinants and toxins under conditions used in a routine laboratory and has the potential to be used for array-based high-throughput screening.
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Affiliation(s)
- S Monecke
- Institute for Medical Microbiology and Hygiene, Faculty of Medicine 'Carl Gustav Carus', Technical University of Dresden, Dresden, Germany.
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Kirner T, Ackermann J, Ehricht R, McCaskill JS. Complex patterns predicted in an in vitro experimental model system for the evolution of molecular cooperation. Biophys Chem 1999; 79:163-86. [PMID: 17030317 DOI: 10.1016/s0301-4622(99)00049-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/1998] [Revised: 01/28/1999] [Accepted: 03/19/1999] [Indexed: 11/19/2022]
Abstract
An isothermal biochemical in vitro amplification system with two trans-cooperatively coupled amplifying DNA molecules was investigated homogeneously using a hierarchy of kinetic models and as a simplified reaction-diffusion system. In our model of this recently developed experimental system, no reaction mechanism higher than second order occurs, yet numerical simulations show a variety of complex spatiotemporal patterns which arise in response to finite amplitude perturbations in a flow reactor. In a certain domain of the kinetic parameters the system shows self-replicating spots. These spots can stabilize the cooperative amplification in such evolving systems against emerging parasites. The results are of high relevance for experimental studies on these functional in vitro ecosystems in spatially resolved microstructured reactors.
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Affiliation(s)
- T Kirner
- Department of Molecular Information Processing, Institute of Molecular Biotechnology, Beutenbergstr. 11, D-07745 Jena, Germany.
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Abstract
BACKGROUND One of the key issues in the investigation of evolution is how complex systems evolved from simple chemical replicators. Theoretical work proposed several models in which complex replicating systems are kinetically stabilized. The development of powerful isothermal amplification technique allows complex nucleic acid based evolving in vitro systems to be set up, which may then serve to verify experimentally current theories of evolution. Recently such a system based on the 3SR (self-sustained sequence replication) reaction has been established to investigate the evolution of cooperation: the trans-cooperatively coupled CATCH (cooperative amplification by cross hybridization). RESULTS Over four rounds of serial transfer, the cooperatively coupled two species CATCH system evolved into a more complex cooperative four species system, which then was overgrown by CATCH-derived RNA-Z-like hairpin species. In contrast to the classical RNA-Z species, these molecules have complementary loop sequences and self-amplify using a dual mechanism that includes concentration-dependent phases of noncooperative and cooperative amplification. CONCLUSIONS The evolution of a cooperative system, under conditions that were alternately unfavorable and favorable for cooperative amplification, led to a system showing facultative cooperation. This principle of facultative cooperation preserves the complexity of the system investigated and could have general implications for the evolution and stabilization of cooperation under oscillating reaction conditions.
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Affiliation(s)
- T Ellinger
- Department of Molecular Information Processing Institute of Molecular Biotechnology Beutenbergstrasse 11 07745 Clondiag Chip Technologies Löbstedter Strasse 105 D 07743 Jena Germany.
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Affiliation(s)
- T Ellinger
- Dept. Molecular Information Processing, Institute of Molecular Biotechnology, Jena, Germany.
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Ehricht R, Kirner T, Ellinger T, Foerster P, McCaskill JS. Monitoring the amplification of CATCH, a 3SR based cooperatively coupled isothermal amplification system, by fluorimetric methods. Nucleic Acids Res 1997; 25:4697-9. [PMID: 9358187 PMCID: PMC147089 DOI: 10.1093/nar/25.22.4697] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Three different types of fluorescence detection methods were employed to monitor amplification of a previously established isothermal cooperatively coupled amplification system as it can serve as a tool for the investigation of fundamental issues in evolutionary optimization. By using 5'IRD-41 fluorescent labeled primers, the intercalating dye TOPRO-1 and a 5'fluorescin/3'DABCYL 4-(4-dimethylamino-phenylazo)benzoic acid labeled ss 24 nt DNA, evolving molecular cooperation is accessible, sequence specifically as well as non-sequence-specifically without using radioactivity.
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Affiliation(s)
- R Ehricht
- Department of Molecular Information Processing, Institute of Molecular Biotechnology, Beutenbergstrasse 11, 07745 Jena, Germany.
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Abstract
In vitro amplification systems not only serve as a tool for the processing of DNA, but have also provided important model systems for the investigation of fundamental issues in evolutionary optimization. In this work we present a coupled amplification system based on the self-sustained sequence replication (3SR), also known as nucleic acid sequence-based amplification (NASBA), which allows the experimental investigation of evolving molecular cooperation. The 3SR reaction is an isothermal method of nucleic acid amplification and an alternative to PCR. A target nucleic acid sequence can be amplified exponentially in vitro using two enzymes: reverse transcriptase (RT) and a DNA-dependent RNA polymerase (RNAP). A system has been constructed in which amplification of two molecular species is cooperatively coupled. These species are single-stranded (ss)DNA templates (D1 and D2) of lengths 58 and 68 nucleotides, respectively. Coupling occurs when D1 and D2 anneal to each other via a complementary region (DB and DB') situated at the 3' end of each template. RT elongates the hybridized templates producing a double-stranded (ds)DNA of 106 base pairs (bp). This double strand contains two promoters, which are situated on either side of, and directly adjacent to DB, and which are oriented towards each other. These promoters specify two RNA transcripts encompassing, respectively, the D1 and D2 portion of the dsDNA. After hybridization of two primers (P1 and P2) to the transcripts (R1 and R2) and reverse transcription, the ss templates D1 and D2 are regenerated. Amplification cycles of D1 and D2 are coupled cooperatively via the common dsDNA intermediate. Under optimized batch conditions the system shows the expected growth phases: exponential, linear and saturation phase. The enzymes of the 3SR cycle tend to misincorporate nucleotides and to produce abortive products. In future experiments, we intend to use the system for studies of evolutionary processes in spatially distributed systems where new strategies for optimization at the molecular level are possible.
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Affiliation(s)
- R Ehricht
- Department of Molecular Information Processing, Institute of Molecular Biotechnology, Jena, Germany.
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Abstract
L(-)-Carnitine:NAD+ oxidoreductase, EC 1.1.1.108, from Agrobacterium sp. catalyzes the oxidation of L(-)-carnitine to 3-dehydrocarnitine as initial step of L(-)-carnitine degradation. The enzyme was purified 76-fold by four chromatographic steps. A high substrate specificity for L(-)-carnitine and NAD+ was observed. The molecular mass of the native enzyme is 114 kDa and it consists of two identical subunits as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The isoelectric point was found to be 5.2-5.4. The optimum temperature is 45 degrees C and the optimum pH for the oxidation and the reduction reaction are 9.5 and 5.5-6.5, respectively. Kinetic parameters and amino-terminal sequence were determined. The oxidation reaction is inhibited by D(+)-carnitine, trimethylamine, several metal ions and cetyltrimethylammoniumbromide (CTAB).
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Affiliation(s)
- H Hanschmann
- Institut für Biochemie, Fakultät für Biowissenschaften, Pharmazie und Psychologie, Universität Leipzig, Germany
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Ehricht R. [Contribution to the construction of resection prostheses in cases of limited oral aperture]. Dtsch Zahnarztl Z 1974; 29:948-9. [PMID: 4609750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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