Peter Slickers

Friedrich Loeffler Institute, Griefswald, Mecklenburg-Vorpommern, Germany

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Publications (45)152.4 Total impact

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    ABSTRACT: It has been shown previously that high rates of methicillin- and mupirocin-resistant Staphylococcus aureus exist in the Caribbean islands of Trinidad and Tobago, as well as a high prevalence of Panton-Valentine leukocidin-positive S. aureus. Beyond these studies, limited typing data have been published. In order to obtain insight into the population structure not only of MRSA but also of methicillin-susceptible S. aureus, 294 clinical isolates collected in 2012/2013 were typed by microarray hybridisation. A total of 15.31% of the tested isolates were MRSA and 50.00% were PVL-positive. The most common MSSA strains were PVL-positive CC8-MSSA (20.41% of all isolates tested), PVL-positive CC152-MSSA (9.52%) and PVL-positive CC30-MSSA (8.84%) while the most common MRSA were ST239-MRSA-III&SCCmer (9.18%) and ST8-MRSA-IV, "USA300" (5.78%). 2.38% of characterised isolates belonged to distinct strains likely to be related to "Staphylococcus argenteus" lineages. The population structure of S. aureus isolates suggests an importation of strains from Africa, endemicity of PVL-positive MSSA (mainly CC8) and of ST239-MRSA-III, and a recent emergence of the PVL-positive CC8-MRSA-IV strain "USA300".
    PLoS ONE 01/2014; 9(2):e89120. · 3.73 Impact Factor
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    ABSTRACT: The PVL-positive ST772-MRSA-V is an emerging community-associated (CA-) MRSA clone that has been named Bengal Bay Clone since most patients have epidemiological connections to the Indian subcontinent. It is found increasingly common in other areas of the world. One isolate of ST772-MRSA-V was sequenced using the Illumina Genome Analyzer System. After initial assembling the multiple sequence contigs were analysed using different in-house annotation scripts. Results were compared to microarray hybridisation results of clinical isolates of ST772-MRSA-V, of related strains and to another ST772-MRSA-V genome sequence. According to MLST e-burst analysis, ST772-MRSA-V belongs to Clonal Complex (CC)1, differing from ST1 only in one MLST allele (pta-22). However, there are several additional differences including agr alleles (group II rather than III), capsule type (5 rather than 8), the presence of the egc enterotoxin gene cluster and of the enterotoxin homologue ORF CM14 as well as the absence of the enterotoxin H gene seh. Enterotoxin genes sec and sel are present. ST772-MRSA-V harbours the genes encoding enterotoxin A (sea) and PVL (lukS/F-PV). Both are located on the same prophage. ST772-MRSA-V may have emerged from the same lineage as globally spread CC1 and CC5 strains. It has acquired a variety of virulence factors, and for a CA-MRSA strain it has an unusually high number of genes associated with antibiotic resistance.
    BMC Research Notes 12/2013; 6(1):548.
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    ABSTRACT: In this study, an improvement of the oligonucleotide-based DNA microarray for the genoserotyping of E. coli is presented. Primer and probes for additional 70 O antigen groups were developed. The microarray was transferred to a new platform, the ArrayStrip format, which allows high through-put tests in 96-well formats and fully automated microarray analysis. Thus, it is possible to determine within a single experiment 94 of the over 180 known O antigen groups as well as 47 of the 53 different H antigens within a few hours starting from a single colony. The microarray was initially validated with a set of defined reference strains that had previously been serotyped by conventional agglutination in various reference centers. For further validation of the microarray, 180 clinical E. coli isolates of human origin (from urine samples, blood cultures, bronchial secretions and wound swabs) and 53 E. coli isolates from cattle, pigs and poultry were used. A high degree of concordance between the results of classical antibody based serotyping and the DNA based genoserotyping was demonstrated during the validation of the new 70 O antigen groups as well as for the field strains of human and animal origin. Therefore, this oligonucleotide array represents a diagnostic tool that is user-friendly and more efficient than the classical serotyping by agglutination. Furthermore, the tests can be performed in almost every routine lab, easily expanded and standardized.
    Microbiology and Immunology 12/2013; · 1.55 Impact Factor
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    ABSTRACT: Methicillin-Resistant Staphylococcus aureus (MRSA) have been a major cause of nosocomial infection in Irish hospitals for four decades and replacement of predominant MRSA clones has occurred several times. An MRSA isolate recovered in 2006 as part of a larger study of sporadic MRSA exhibited a rare spa (t878) and multilocus-sequence (ST779) type and was non-typeable by PCR- and DNA microarray-based SCCmec typing. Whole-genome sequencing revealed the presence of a novel 51 kb composite element (CI) with three distinct domains, each flanked by direct repeat and inverted repeat sequences, including (i) a pseudo SCCmec element (16.3 kb) encoding mecA with a novel mec class region, a fusidic acid resistance gene (fusC) and two copper resistance genes (copB and copC), but lacking ccr genes, (ii) a SCC element (17.5 kb) encoding a novel ccrAB4 allele and (iii) a SCCelement (17.4 kb) encoding a novel ccrC allele and a clustered regularly interspaced short palindromic repeat (CRISPR) region. The novel CI was subsequently identified by PCR in an additional 13 t878/ST779-MRSA isolates, six from bloodstream infections, recovered between 2006-2011 in eleven hospitals. Analysis of open reading frames (ORFs) encoded by the CI showed amino acid sequence similarity between 44-100% with ORFs from S. aureus and coagulase-negative staphylococci (CoNS). These findings provide further evidence of genetic transfer between S. aureus and CoNS and how this contributes to the emergence of novel SCCmec elements and MRSA strains. Ongoing surveillance of this MRSA strain is warranted and will require updating of currently used SCCmec typing methods.
    Antimicrobial Agents and Chemotherapy 11/2012; · 4.57 Impact Factor
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    ABSTRACT: To gain insight into the genomic diversity of Staphylococcus aureus associated with diseases in domestic poultry, 131 isolates from clinically ill turkeys (n=80) and chickens (n=51) were collected and genotyped using microarray hybridisations. MRSA isolates were subjected to spa and dru typing and their antimicrobial resistance geno- and phenotypes were determined. Most (68 out of 80) turkey isolates belonged to the clonal complex (CC) 398. Seventeen of the 80 isolates (21.2%) were MRSA. The most common MRSA type among turkeys was CC398-MRSA-V (n=8), but CC5-MRSA-III (n=4), CC9-MRSA-IV (n=2), CC398-MRSA-IV (n=2) and a single CC398-MRSA with an unidentified/truncated SCCmec element were also found. Among the chicken isolates, CC5 predominated (44 out of 51). Five of the chicken isolates were MRSA (9.8%), all belonging to CC398-MRSA-V. These data show that the current dissemination of livestock-associated MRSA also engulfs chickens and turkeys, and that MRSA surveillance among these species is warranted.
    Veterinary Microbiology 10/2012; · 3.13 Impact Factor
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    ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) is spreading worldwide and poses a serious public health problem, being present in hospital settings and communities. However, from the Middle East and the Arabian Peninsula few molecular typing data on MRSA strains are currently available. In order to obtain data on the population structure of MRSA in Riyadh, Saudi Arabia, 107 clinical and environmental MRSA isolates were genotyped using a microarray-based assay. Five major MRSA strains from four clonal complexes were identified CC8/ST239-III (20.75%), PVL-positive as well as -negative CC22-IV (18.87% and 9.43%, respectively), PVL-positive CC30-IV (12.26%) and PVL-positive CC80-IV (17.92%). Minor strains, which accounted for less than 3% each, included CC1-IV/SCCfus, PVL-positive CC1/ST772-V, PVL-positive as well as- negative CC5-IV, CC5-IV/SCCfus, CC5-V, CC6-IV, CC45-IV, PVL-negative CC80-IV, PVL-positive CC88-IV, CC97-V and a CC9/ST834-MRSA strain. Typing of MRSA strains from Riyadh revealed a high diversity of clonal complexes. The prevalence of the genes encoding the Panton-Valentine leukocidin was surprisingly high (54.21%), and a significant rate of resistance markers was detected also in strains considered as community-associated.
    BMC Microbiology 07/2012; 12:146. · 3.10 Impact Factor
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    ABSTRACT: The recently described phenol-soluble modulin PSM-mec was detected in Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus fleuretti, Staphylococcus hominis, Staphylococcus pseudintermedius, Staphylococcus saprophyticus, Staphylococcus simulans and Staphylococcus vitulinus from different hosts (humans, goats, dogs, cats, pigs, cattle and turkeys). It was identified in isolates harbouring SCCmec types II, IIA, IIB, IID, III, VIII and in some irregular or truncated elements.
    Molecular and Cellular Probes 01/2012; 26(2):99-103. · 1.87 Impact Factor
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    ABSTRACT: Salmonellosis caused by Salmonella (S.) belongs to the most prevalent food-borne zoonotic diseases throughout the world. Therefore, serotype identification for all culture-confirmed cases of Salmonella infection is important for epidemiological purposes. As a standard, the traditional culture method (ISO 6579:2002) is used to identify Salmonella. Classical serotyping takes 4-5 days to be completed, it is labor-intensive, expensive and more than 250 non-standardized sera are necessary to characterize more than 2,500 Salmonella serovars currently known. These technical difficulties could be overcome with modern molecular methods. We developed a microarray based serogenotyping assay for the most prevalent Salmonella serovars in Europe and North America. The current assay version could theoretically discriminate 28 O-antigens and 86 H-antigens. Additionally, we included 77 targets analyzing antimicrobial resistance genes. The Salmonella assay was evaluated with a set of 168 reference strains representing 132 serovars previously serotyped by conventional agglutination through various reference centers. 117 of 132 (81%) tested serovars showed an unique microarray pattern. 15 of 132 serovars generated a pattern which was shared by multiple serovars (e.g., S. ser. Enteritidis and S. ser. Nitra). These shared patterns mainly resulted from the high similarity of the genotypes of serogroup A and D1. Using patterns of the known reference strains, a database was build which represents the basis of a new PatternMatch software that can serotype unknown Salmonella isolates automatically. After assay verification, the Salmonella serogenotyping assay was used to identify a field panel of 105 Salmonella isolates. All were identified as Salmonella and 93 of 105 isolates (88.6%) were typed in full concordance with conventional serotyping. This microarray based assay is a powerful tool for serogenotyping.
    PLoS ONE 01/2012; 7(10):e46489. · 3.73 Impact Factor
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    ABSTRACT: Two isolates of enterohemorrhagic Escherichia coli (EHEC) O104:H4 were isolated in France in 2004 and 2009. Both were characterized and compared to the strain which caused the German outbreak in 2011 and to other O104:H4 strains. This suggests that different O104:H4 EHEC strains were present several years prior to the 2011 outbreak.
    Applied and environmental microbiology 12/2011; 77(24):8784-6. · 3.69 Impact Factor
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    ABSTRACT: Eighty methicillin-resistant Staphylococcus aureus (MRSA) isolates from three hospitals in Trinidad and Tobago were collected and genotyped using microarray hybridisation. They were found to belong to three distinct MRSA strains. Of the 80 isolates, 76 were assigned to ST239-MRSA-III. They were largely homogeneous, although some variations affected the presence of the enterotoxin A gene, as well as of resistance markers (mercury resistance operon, aadD, tet(K), qacA). The mupA gene conferring mupirocin resistance was found in 7.3% of isolates. One isolate was identified as CC5-MRSA-II and three isolates belonged to the Panton-Valentine leukocidin (PVL)-positive ST8-MRSA-IV strain USA300. While community-acquired MRSA strains are rare in Trinidad and Tobago, the vast majority of MRSA cases can be attributed to healthcare-associated strains. Thus, infection control procedures within medical facilities need to be revised and enforced. This could substantially reduce the burden of MRSA to healthcare in Trinidad and Tobago.
    European Journal of Clinical Microbiology 11/2011; 31(7):1497-500. · 3.02 Impact Factor
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    ABSTRACT: Methicillin resistance in staphylococci is mediated by penicillin binding protein 2a (PBP 2a), encoded by mecA on mobile staphylococcal cassette chromosome mec (SCCmec) elements. In this study, two clonal complex 130 (CC130) methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients in Irish hospitals were identified that were phenotypically PBP 2a positive but lacked mecA by conventional PCR and by DNA microarray screening. The isolates were identified as methicillin-susceptible S. aureus using the GeneXpert real-time PCR assay. Whole-genome sequencing of one isolate (M10/0061) revealed a 30-kb SCCmec element encoding a class E mec complex with highly divergent blaZ-mecA-mecR1-mecI, a type 8 cassette chromosome recombinase (ccr) complex consisting of ccrA1-ccrB3, an arsenic resistance operon, and flanking direct repeats (DRs). The SCCmec element was almost identical to that of SCCmec type XI (SCCmec XI) identified by the Sanger Institute in sequence type 425 bovine MRSA strain LGA251 listed on the website of the International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements. The open reading frames (ORFs) identified within SCCmec XI of M10/0061 exhibited 21 to 93% amino acid identity to ORFs in GenBank. A third DR was identified ca. 3 kb downstream of SCCmec XI, indicating the presence of a possible SCC remnant. SCCmec XI was also identified in the second CC130 MRSA isolate by PCR and sequencing. The CC130 MRSA isolates may be of animal origin as previously reported CC130 S. aureus strains were predominantly from bovine sources. The highly divergent nature of SCCmec XI relative to other SCCmec elements indicates that it may have originated in another taxon.
    Antimicrobial Agents and Chemotherapy 06/2011; 55(8):3765-73. · 4.57 Impact Factor
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    ABSTRACT: To investigate the occurrence of antimicrobial resistance genes of human clinical relevance in Salmonella isolated from livestock in Great Britain. Two hundred and twenty-five Salmonella enterica isolates were characterized using an antimicrobial resistance gene chip and disc diffusion assays. Plasmid profiling, conjugation experiments and identification of Salmonella genomic island 1 (SGI1) were performed for selected isolates. Approximately 43% of Salmonella harboured single or multiple antimicrobial resistance genes with pig isolates showing the highest numbers where 96% of Salmonella Typhimurium harboured one or more resistance genes. Isolates harbouring multiple resistances divided into three groups. Group 1 isolates harboured ampicillin/streptomycin/sulphonamide/tetracycline resistance and similar phenotypes. This group contained isolates from pigs, cattle and poultry that were from several serovars including Typhimurium, 4,[5],12:i:-, Derby, Ohio and Indiana. All Group 2 isolates were from pigs and were Salmonella Typhimurium. They contained a non-sul-type class 1 integron and up to 13 transferrable resistances. All Group 3 isolates harboured a class 1 integron and were isolated from all animal species included in the study. Most isolates were Salmonella Typhimurium and harboured SGI1. Salmonella isolated from livestock was shown to harbour antimicrobial resistance genes although no or little resistance to third-generation cephalosporins or ciprofloxacin, respectively, was detected. The preponderance in pigs of multidrug-resistant Salmonella Typhimurium makes it important to introduce control measures such as improved biosecurity to ensure that they do not pass through the food chain and limit human therapeutic options.
    Journal of Antimicrobial Chemotherapy 03/2011; 66(3):550-9. · 5.34 Impact Factor
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    ABSTRACT: Staphylococcus aureus is a common cause of mastitis and other diseases in camels. In order to obtain data on population structure as well as on the carriage of toxin genes and resistance markers, a collection of 45 isolates from dromedaries of Dubai, United Arab Emirates, were genotyped. These isolates belonged to clonal complexes CC6 (twenty isolates; 44.44%), CC30 (sixteen isolates; 35.56%), CC188 (five isolates; 11.11%), CC152 (1 isolate, 2.2%) and to a previously un-described sequence type (ST1755: arcc-18, aroe-115, glpf-6, gmk-2 pta-109, tpi-50 and yqil-2; three isolates; 6.67%). Resistance genes proved to be rare. Only three out of 45 isolates (6.67%) carried the beta-lactamase operon. The tetracycline resistance gene tetK was also detected in three isolates (6.67%). Neither the mecA gene, defining MRSA, nor other resistance genes were found. Common virulence markers included leukocidin genes lukD+lukE (in twenty-five isolates; 55.56%), the staphylokinase gene sak (twenty-two isolates; 48.89%), the enterotoxin gene cluster egc (fifteen isolates; 33.33%), and a distinct variant of the enterotoxin A gene (sea-320E, GenBank AY196686.1; thirteen isolates; 28.89%). One CC152 isolate was positive for genes encoding the Panton-Valentine leukocidin (lukF-PV+lukS-PV). This study provides first genotyping data on the population structure and the presence of toxin genes and resistance markers of S. aureus strains in Middle Eastern camels.
    Veterinary Microbiology 02/2011; 150(3-4):309-14. · 3.13 Impact Factor
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    ABSTRACT: In recent years, methicillin-resistant Staphylococcus aureus (MRSA) have become a truly global challenge. In addition to the long-known healthcare-associated clones, novel strains have also emerged outside of the hospital settings, in the community as well as in livestock. The emergence and spread of virulent clones expressing Panton-Valentine leukocidin (PVL) is an additional cause for concern. In order to provide an overview of pandemic, epidemic and sporadic strains, more than 3,000 clinical and veterinary isolates of MRSA mainly from Germany, the United Kingdom, Ireland, France, Malta, Abu Dhabi, Hong Kong, Australia, Trinidad & Tobago as well as some reference strains from the United States have been genotyped by DNA microarray analysis. This technique allowed the assignment of the MRSA isolates to 34 distinct lineages which can be clearly defined based on non-mobile genes. The results were in accordance with data from multilocus sequence typing. More than 100 different strains were distinguished based on affiliation to these lineages, SCCmec type and the presence or absence of PVL. These strains are described here mainly with regard to clinically relevant antimicrobial resistance- and virulence-associated markers, but also in relation to epidemiology and geographic distribution. The findings of the study show a high level of biodiversity among MRSA, especially among strains harbouring SCCmec IV and V elements. The data also indicate a high rate of genetic recombination in MRSA involving SCC elements, bacteriophages or other mobile genetic elements and large-scale chromosomal replacements.
    PLoS ONE 01/2011; 6(4):e17936. · 3.73 Impact Factor
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    ABSTRACT: Worldwide, methicillin-resistant Staphylococcus aureus (MRSA) pose an increased risk for healthcare- and community-associated infections. Since the first report of MRSA in England in 1961, several distinct clones or strains have emerged. Changes within the MRSA population of whole countries, small regions or of single hospitals have been observed with some clones replacing others. In this study, the clonal replacement of MRSA isolates in a South-eastern German tertiary care hospital between 2000 and 2010 is described based on microarray analyses of 778 isolates and at least 50 MRSA per year. Within these eleven years, four common epidemic strains, CC22-MRSA-IV, CC45-MRSA-IV, CC5/ST228-MRSA-I (including a variant with a truncated SCCmec element) and CC5-MRSA-II were identified. The PVL-negative CC22-MRSA-IV strain (Barnim Epidemic Strain, UK-EMRSA-15) was detected for the first time in 2001 and its abundance increased since then to 58.6% in 2010. CC5-MRSA-II increased from 2% (2000) to about 30% (2003), and since then it fluctuates between 23 and 37% of isolates. CC5/ST228-MRSA-I decreased from about the half of tested isolates (2000) to 2.3% (2010). A similar trend was observed for CC45-MRSA-IV, which decreased drastically down to 3.4% in 2010 after reaching a maximum of 62.0% in 2002. Seventeen other PVL-negative MRSA strains were identified sporadically with no significant trend being observed. Seven PVL-positive MRSA strains were found, but they remained rare during the study period accounting together for 2.7% of isolates.
    PLoS ONE 01/2011; 6(11):e28189. · 3.73 Impact Factor
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    ABSTRACT: Current typing methods of Chlamydia (C.) trachomatis are mainly based on the diversity of the ompA gene, which is coding for the major outer membrane protein A. The present study aimed at facilitating genotyping of strains of this obligate intracellular human pathogen by developing a DNA microarray assay using the ArrayTube™ format for individual samples and the ArrayStrip™ format for higher throughput. The new test is exploiting multiple discriminatory sites by involving a total of 61 oligonucleotide probes representing genotype-specific polymorphisms in variable domains 1, 2 and 4 of the ompA gene. After multiplex amplification of these domains using biotinylated primers, the sample is hybridized in the microarray vessel under highly stringent conditions. The resulting binding pattern is genotype specific, thus allowing direct identification. We were able to show that DNA from each of the currently accepted genotypes (serovars) yielded a unique, theoretically expected and distinct hybridization pattern. The assay was also shown to be highly sensitive as a dilution containing the equivalent of 1 inclusion-forming unit was still correctly genotyped. In addition, when 62 clinical samples were examined and compared to PCR-RFLP typing results, the genotype was correctly identified by the DNA microarray in all cases. The present test is easy to handle and economically affordable, and it allows genotyping of C. trachomatis to be accomplished within a working day, thus lending itself for epidemiological studies and routine diagnosis.
    Molecular and Cellular Probes 10/2010; 25(1):19-27. · 1.87 Impact Factor
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    ABSTRACT: The staphylococcal cfr gene mediates resistance to phenicols, lincosamides, oxazolidinones, pleuromutilins, and streptogramin A, a phenotype that has been termed PhLOPS(A). The cfr gene has mainly been associated with coagulase-negative staphylococcal isolates from animals, and only a few cfr-positive methicillin-resistant Staphylococcus aureus (MRSA) isolates have been described so far. This study reports the first description of a cfr-positive MRSA isolate (M05/0060) belonging to the pandemic Panton-Valentine leukocidin (PVL)-positive sequence type 8 MRSA IVa/USA300 (ST8-MRSA-IVa/USA300) clone. The cfr gene was detected in M05/0060 using a DNA microarray which was used to screen PVL-positive MRSA isolates for the presence of virulence genes, typing markers, and antimicrobial resistance genes. Antimicrobial susceptibility testing revealed that M05/0060 exhibited the cfr-associated resistance phenotype. Molecular analysis identified the presence of cfr and a second phenicol resistance gene, fexA, on a novel 45-kb conjugative plasmid, which was designated pSCFS7. Within pSCFS7, a DNA segment consisting of cfr, a truncated copy of insertion sequence IS21-558, and a region with homology to the DNA invertase gene bin3 of transposon Tn552 from Bacillus mycoides was integrated into the transposase gene tnpB of the fexA-carrying transposon Tn558. The emergence of a multidrug-resistant cfr-positive variant of ST8-MRSA-IVa/USA300 is alarming and requires ongoing surveillance. Moreover, the identification of a novel conjugative plasmid carrying the cfr gene indicates the ability of cfr to spread to other MRSA strains.
    Antimicrobial Agents and Chemotherapy 10/2010; 54(12):4978-84. · 4.57 Impact Factor
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    ABSTRACT: Clonal complex 59 (CC59) community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains were characterized using pulsed-field gel electrophoresis, spa typing, multilocus sequence typing, diagnostic DNA microarrays, and PCRs targeting staphylococcal cassette chromosome mec (SCCmec) elements and Panton-Valentine leukocidin (PVL). Six distinct groups within CC59 were characterized. At least seven different variants of SCCmec elements were identified (IVa [2B], IVb [2B], IVd [2B], IV variant [2B], IVa [2B&5], V variant [5C2], and V [5C2&5]). (The structural type is indicated by a Roman numeral, with a lowercase letter indicating the subtype, and the ccr complex and the mec complex are indicated by an Arabic numeral and an uppercase letter, respectively. Where there is an extra ccr element, this is indicated by "&" and an Arabic numeral designating the ccr type.) The first group is similar to the American sequence type 59 (ST59) MRSA-IV CA-MRSA strain USA1000. The second group includes a PVL-negative ST87 strain with an SCCmec element of subtype IVb (2B). The third group comprises PVL-variable ST59 MRSA-IV strains harboring multiple SCCmec IV subtypes. PVL-negative ST59 MRSA strains with multiple or composite SCCmec elements (IVa [2B&5]) form the fourth group. Group 5 corresponds to the internationally known "Taiwan clone," a PVL-positive strain with a variant SCCmec element (V [5C2&5]). This strain proved to be the most common CC59 MRSA strain isolated in Western Australia. Finally, group 6 encompasses the ST59 MRSA-V variant (5C2). The differentiation of CC59 into groups and strains indicates a rapid evolution and spread of SCCmec elements. Observed differences between groups of strains as well as intrastrain variability within a group facilitate the tracing of their spread.
    Antimicrobial Agents and Chemotherapy 03/2010; 54(5):1914-21. · 4.57 Impact Factor
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    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.
    European Journal of Clinical Microbiology 02/2010; 29(4):457-63. · 3.02 Impact Factor
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    ABSTRACT: Community-acquired methicillin-resistant Staphylococcus aureus have become a major problem in Australia. These strains have now been isolated throughout Australia including remote Indigenous communities that have had minimal exposure to healthcare facilities. Some of these strains, belonging to sequence types ST75 and ST883, have previously been reported to harbour highly divergent alleles of the housekeeping genes used in multilocus sequence typing. ST75-MRSA-IV and ST883-MRSA-IV isolates were characterised in detail. Morphological features as well as 16S sequences were identical to other S. aureus strains. Although a partial rnpB gene sequence was not identical to previously known S. aureus sequences, it was found to be more closely related to S. aureus than to other staphylococci. Isolates also were screened using diagnostic DNA microarrays. These isolates yielded hybridisation results atypical for S. aureus. Primer directed amplification assays failed to detect species markers (femA, katA, sbi, spa). However, arbitrarily primed amplification indicated the presence of unknown alleles of these genes. Isolates could not be assigned to capsule types 1, 5 or 8. The allelic group of the accessory gene regulator (agr) locus was not determinable. Sequencing of a region of agrB, agrC and agrD (approximately 2,100 bp) revealed a divergent sequence. However, this sequence is more related to S. aureus agr alleles I and IV than to agr sequences from other Staphylococcus species. The predicted auto-inducing peptide (AIP) sequence of ST75 was identical to that of agr group I, while the predicted AIP sequence of ST883 was identical to agr group IV. The genetic properties of ST75/ST883-MRSA may be due to a series of evolutionary events in ancient insulated S. aureus strains including a convergent evolution leading to agr group I- or IV-like AIP sequences and a recent acquisition of SCCmec IV elements.
    PLoS ONE 01/2010; 5(11):e14025. · 3.73 Impact Factor

Publication Stats

1k Citations
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152.40 Total Impact Points

Institutions

  • 2006–2013
    • Friedrich Loeffler Institute
      • • Institute of Epidemiology
      • • Institute of Molecular Pathogenesis
      • • Institute of Bacterial Infections and Zoonoses
      Griefswald, Mecklenburg-Vorpommern, Germany
    • Friedrich-Schiller-University Jena
      • Institut für Biochemie und Biophysik
      Jena, Thuringia, Germany
  • 2010–2012
    • Trinity College Dublin
      • Division of Oral Biosciences
      Dublin, L, Ireland
  • 2006–2012
    • Technische Universität Dresden
      • • Institut für Mikrobiologie
      • • Medizinische Fakultät Carl Gustav Carus
      Dresden, Saxony, Germany
  • 2011
    • St. James's Hospital
      • Department of Clinical Microbiology
      Dublin, Leinster, Ireland
  • 2008
    • University of Zurich
      • Institute of Veterinary Pathology
      Zürich, ZH, Switzerland
  • 2007
    • Universität Bern
      • Institute of Veterinary Bacteriology
      Berna, Bern, Switzerland