title: Diversity of SCCmec Elements in Staphylococcus aureus as Observed in South-Eastern Germany.
abstract: SCCmec elements are very important mobile genetic elements in Staphylococci that carry beta-lactam resistance genes mecA/mecC, recombinase genes and a variety of accessory genes. Twelve main types and a couple of variants have yet been described. In addition, there are also other SCC elements harbouring other markers. In order to subtype strains of methicillin-resistant S. aureus (MRSA) based on variations within their SCCmec elements, 86 markers were selected from published SCC sequences for an assay based on multiplexed primer extension reactions followed by hybridisation to the specific probes. These included mecA/mecC, fusC, regulatory genes, recombinase genes, genes from ACME and heavy metal resistance loci as well as several genes of unknown function. Hybridisation patterns for published genome or SCC sequences were theoretically predicted. For validation of the microarray based assay and for stringent hybridisation protocol optimization, real hybridization experiments with fully sequenced reference strains were performed modifying protocols until yielded the results were in concordance to the theoretical predictions. Subsequently, 226 clinical isolates from two hospitals in the city of Dresden, Germany, were characterised in detail. Beside previously described types and subtypes, a wide variety of additional SCC types or subtypes and pseudoSCC elements were observed as well as numerous composite elements. Within the study collection, 61 different such elements have been identified. Since hybridisation cannot recognise the localisation of target genes, gene duplications or inversions, this is a rather conservative estimate. Interestingly, some widespread epidemic strains engulf distinct variants with different SCCmec subtypes. Notable examples are ST239-MRSA-III, CC5-, CC22-, CC30-, and CC45-MRSA-IV or CC398-MRSA-V. Conversely, identical SCC elements were observed in different strains with SCCmec IVa being spread among the highest number of Clonal Complexes. The proposed microarray can help to distinguish isolates that appear similar or identical by other typing methods and it can be used as high-throughput screening tool for the detection of putative new SCC types or variants that warrant further investigation and sequencing. The high degree of diversity of SCC elements even within so-called strains could be helpful for epidemiological typing. It also raises the question on scale and speed of the evolution of SCC elements.
authors.affiliation: Institute for Medical Microbiology and Hygiene (IMMH), Technische Universität Dresden, Dresden, Germany.|Alere Technologies GmbH, Jena, Germany.|InfectoGnostics Research Campus, Jena, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Monecke
authors.affiliation: Department of Hospital Infection Control, Dresden University Hospital, Dresden, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Jatzwauk
authors.affiliation: Alere Technologies GmbH, Jena, Germany.|InfectoGnostics Research Campus, Jena, Germany.
authors.forename: Elke
authors.initials: E
authors.lastname: Müller
authors.affiliation: Department of Laboratory Medicine, Hospital Dresden Neustadt, Dresden, Germany.
authors.forename: Hedda
authors.initials: H
authors.lastname: Nitschke
authors.affiliation: Institute for Medical Microbiology and Hygiene (IMMH), Technische Universität Dresden, Dresden, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Pfohl
authors.affiliation: Alere Technologies GmbH, Jena, Germany.|InfectoGnostics Research Campus, Jena, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Slickers
authors.affiliation: Alere Technologies GmbH, Jena, Germany.|InfectoGnostics Research Campus, Jena, Germany.
authors.forename: Annett
authors.initials: A
authors.lastname: Reissig
authors.affiliation: Institute for Medical Microbiology and Hygiene (IMMH), Technische Universität Dresden, Dresden, Germany.
authors.forename: Antje
authors.initials: A
authors.lastname: Ruppelt-Lorz
authors.affiliation: Alere Technologies GmbH, Jena, Germany.|InfectoGnostics Research Campus, Jena, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Ehricht
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques / Q000379:methods; D004251:DNA Transposable Elements / Q000235:genetics*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D014644:Genetic Variation; D005858:Germany; D006801:Humans; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000502:physiology; D046915:Penicillin-Binding Proteins / Q000235:genetics; D015203:Reproducibility of Results; D013203:Staphylococcal Infections / Q000382:microbiology; D013211:Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D046915:Penicillin-Binding Proteins; C487789:mecA protein, Staphylococcus aureus