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Keiichi Hiramatsu - One of the best experts on this subject based on the ideXlab platform.
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Staphylococcal Cassette Chromosome mec (SCCmec) analysis of MRSA.
Methods in Molecular Biology, 2013Co-Authors: Teruyo Ito, Yuki Katayama, Yoko Kondo, Kyoko Kuwahara-arai, Yuki Uehara, Xiao Han, Keiichi HiramatsuAbstract:Methicillin-susceptible S. aureus (MSSA) changes to methicillin-resistant S. aureus upon the acquisition of Staphylococcal Cassette Chromosome mec (SCCmec), a genomic island that encodes methicillin resistance. All SCCmec elements reported to date share four common characteristics: (1) carrying the mec gene complex (mec); (2) carrying the ccr gene complex (ccr); (3) being flanked by characteristic nucleotide sequences, inverted repeats, and direct repeats, at both ends; and (4) being integrated at the integration site sequence (ISS) for SCC, which is located at the 3'-end of orfX or at the extremity of the SCC element. SCCmec elements in S. aureus are classified into different types based on the combination of mec and ccr, which share variations, five classes in mec and eight in ccr. To date, at least 11 types of SCCmec elements have been identified. Regions other than mec and ccr within the SCCmec element are designated as "joining regions" (J-regions), which are classified into three subgroups, J1-3. Many J-region variants have been identified among the SCCmec elements of types I-V. We herein describe PCR methods to type SCCmec elements by first identifying the mec and ccr type, and then identifying genes in the J-regions.
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Classification of staphylococcal cassette chromosome mec (SCCmec) : guidelines for reporting novel SCCmec elements.
Antimicrobial Agents and Chemotherapy, 2009Co-Authors: Teruyo Ito, David C Coleman, Frances G. O'brien, Keiichi Hiramatsu, Henrik Westh, D. Oliviera, H. De Lencastre, K. Zhang, Philip M. Giffard, Fred C. TenoverAbstract:Classification of staphylococcal cassette chromosome mec (SCCmec) : guidelines for reporting novel SCCmec elements.
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A novel gene, fudoh, in the SCCmec region suppresses the colony spreading ability and virulence of Staphylococcus aureus.
PLoS ONE, 2008Co-Authors: Chikara Kaito, Teruyo Ito, Keiichi Hiramatsu, Yosuke Omae, Yasuhiko Matsumoto, Makiko Nagata, Hiroki Yamaguchi, Taiji Aoto, Kazuhisa SekimizuAbstract:Staphylococcus aureus colonies can spread on soft agar plates. We compared colony spreading of clinically isolated methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). All MSSA strains showed colony spreading, but most MRSA strains (73%) carrying SCCmec type-II showed little colony spreading. Deletion of the entire SCCmec type-II region from these MRSA strains restored colony spreading. Introduction of a novel gene, fudoh, carried by SCCmec type-II into Newman strain suppressed colony spreading. MRSA strains with high spreading ability (27%) had no fudoh or a point-mutated fudoh that did not suppress colony spreading. The fudoh-transformed Newman strain had decreased exotoxin production and attenuated virulence in mice. Most community-acquired MRSA strains carried SCCmec type-IV, which does not include fudoh, and showed high colony spreading ability. These findings suggest that fudoh in the SCCmec type-II region suppresses colony spreading and exotoxin production, and is involved in S. aureus pathogenesis.
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Type IV SCCmec found in decade old Brazilian MRSA isolates
Brazilian Journal of Infectious Diseases, 2008Co-Authors: Cristina Reinert, John A. Mcculloch, Shinya Watanabe, Teruyo Ito, Keiichi Hiramatsu, Elsa Masae MamizukaAbstract:Methicillin-resistant Staphylococcus aureus (MRSA) commonly causes infection in hospitalized patients. Since its appearance in the 1960s, the SCCmec has evolved throughout the years into 5 different types (I-V), each bearing a different set of genes. Infection with MRSA SCCmec types I, II or III is almost exclusively restricted to hospitalised patients. However, recently, community acquired MRSA (CA-MRSA) infections have been reported with increasing frequency, usually caused by a type IV SCCmec MRSA in nosocomial settings. We studied the prevalence of SCCmec types in 50 nosocomial strains collected from 1995 to 1999. The SCCmec complex type and presence of Panton-Valentine leukocidin (PVL) were determined by PCR. Strains had been previously typed by PFGE and were now typed by MLST. We found that 3 of the isolates studied bore a type IVc SCCmec all having different PFGE and MLST profiles (ST3, ST5 and ST88). All strains bearing a type III SCCmec belonged to MLST ST239 (Brazilian/Iberian clone). Only the strain which presented the ST5 profile bore the pvl gene. The type IVc SCCmec strains presented relatively lower levels of resistance to oxacillin in comparison to the type III SCCmec strains. The pattern of dissemination of the type IV SCCmec remains to be elucidated. The finding of strains carrying a type IV SCCmec in the present study among strains isolated at least 7 years ago indicates that clones bearing a type IV SCCmec have been present in Brazil for quite some time, and must have gone by undetected.
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combination of multiplex pcrs for staphylococcal cassette chromosome mec type assignment rapid identification system for mec ccr and major differences in junkyard regions
Antimicrobial Agents and Chemotherapy, 2007Co-Authors: Yoko Kondo, Shinya Watanabe, Barry N Kreiswirth, Jerome Etienne, Keiichi HiramatsuAbstract:Staphylococcal cassette chromosome mec (SCCmec) typing, in combination with genotyping of the Staphylococcus aureus chromosome, has become essential for defining methicillin-resistant S. aureus (MRSA) clones in epidemiological studies. We have developed a convenient system for SCCmec type assignment. The system consists of six multiplex PCRs (M-PCRs) for identifying the ccr gene complex (ccr), the mec gene complex (mec), and specific structures in the junkyard (J) regions: M-PCR with primer set 1 (M-PCR 1) identified five types of ccr genes; M-PCR 2 identified class A to class C mec; M-PCRs 3 and 4 identified specific open reading frames in the J1 regions of type I and IV and of type II, III, and V SCCmec elements, respectively; M-PCR 5 identified the transposons Tn554 and ΨTn554 integrated into the J2 regions of type II and III SCCmec elements; and M-PCR 6 identified plasmids pT181 and pUB110 integrated into J3 regions. The system was validated with 99 MRSA strains carrying SCCmec elements of different types. The SCCmec types of 93 out of the 99 MRSA strains could be assigned. The SCCmec type assignments were identical to those made with a PCR system that uses numerous primer pairs to identify genes or gene alleles. Our system of six M-PCRs is thus a convenient and reliable method for typing SCCmec elements.
Jangjih Lu - One of the best experts on this subject based on the ideXlab platform.
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characterization of two novel variants of staphylococcal cassette chromosome mec elements in oxacillin resistant staphylococcus lugdunensis
Journal of Antimicrobial Chemotherapy, 2017Co-Authors: Shihcheng Chang, Chengmao Ho, Jangjih LuAbstract:Objectives: Staphylococcus lugdunensis, a species of CoNS, has become an important hospital pathogen because of increasing resistance to β-lactam antibiotics such as methicillin and oxacillin. Methicillin resistance is mainly due to the acquisition of the staphylococcal cassette chromosome (SCC) mec (SCCmec). Little is known about the structure of SCCmec in methicillin- or oxacillin-resistant CoNS. Methods: WGS was performed to determine the structure of SCCmec elements of two clinical S. lugdunensis isolates: CMUH-22 and CMUH-25. Results: These elements were found to be flanked by DRs and IRs with unique mosaic structures and a common integration site in the 3' end of the rlmH gene. The sequences of the regions located between rlmH and the ISSau4-like transposase genes of both elements were similar to those of SCCmec Vt of Staphylococcus aureus PM1. The SCCmec (type V, 5C2&4) of CMUH-25 harboured a novel ccrC complex and a C2-like mec complex in opposite orientations, similar to the type V SCCmec of S. aureus WIS. The sequences of the ccrA4B4 genes and J1 and J2 regions of CMUH-25 were similar to those of the SCC element of Staphylococcus haemolyticus NCTC 11042. In contrast, portions of the sequence of the J1 region of type Vt (5C2) SCCmec in strain CMUH-22 were highly similar to portions of those of Staphylococcus epidermidis RP62A and the composite SCCmec type V of S. aureus WAMRSA40. Conclusions: These observations suggest that the SCCmec elements of CMUH-25 and CMUH-22 evolved separately and assembled through different recombination events.
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molecular characteristics of disease causing and commensal staphylococcus lugdunensis isolates from 2003 to 2013 at a tertiary hospital in taiwan
PLOS ONE, 2015Co-Authors: Chunwen Cheng, Shihcheng Chang, Jangjih LuAbstract:Objectives Staphylococcus lugdunensis can cause community- and healthcare-associated infections. This study investigated the molecular characteristics of S. lugdunensis isolates collected at our hospital and compared the characteristics of the infectious and commensal isolates. Methods We collected the S. lugdunensis isolates between 2003 and 2013. The antimicrobial resistance test, SCCmec typing, accessory gene regulator (agr) typing, pulsed-field gel electrophoresis (PFGE), and δ-like hemolysin activity were performed. Results In total, 118 S. lugdunensis isolates were collected, of which 67 (56.8%) were classified into the infection group and 51 (43.2%) into the commensal group. The oxacillin resistance rate was 36.4%. The most common SCCmec types were SCCmec types V (51.4%) and II (32.6%). In total, 34 pulsotypes were identified. The PFGE typing revealed five clones (pulsotypes A, J, M, N, and P) at our hospital. Pulsotypes A and N caused the spread of high oxacillin resistance. In total, 10.2% (12 of 118) of the isolates lacked δ-like hemolysin activity. Compared with the infection group, the commensal group showed a higher percentage of multiple drug resistance and carried a higher percentage of SCCmec type II (11 of 22, 50% and 3 of 21, 14.3%) and a lower percentage of SCCmec type V (8 of 22, 36.4% and 14 of 21, 66.7%). The commensal group (27 PFGE types) showed higher genetic diversity than did the infection group (20 PFGE types). No difference was observed in the distribution of the five main pulsotypes, agr typing, and the presence of δ-like hemolysin activity between the two groups. Conclusions Five main clones were identified at our hospital. The commensal group showed higher genetic diversity, had a higher percentage of multidrug resistance, and carried a higher percentage of SCCmec type II and a lower percentage of SCCmec type V than did the infection group.
Norihisa Noguchi - One of the best experts on this subject based on the ideXlab platform.
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increase in SCCmec type iv strains affects trends in antibiograms of meticillin resistant staphylococcus aureus at a tertiary care hospital
Journal of Medical Microbiology, 2015Co-Authors: Ayumu Ito, Hidemasa Nakaminami, Takeshi Fujii, Kenta Utsumi, Norihisa NoguchiAbstract:The prevalence of community-acquired meticillin-resistant Staphylococcus aureus (CA-MRSA) strains has become a serious problem worldwide. The aim of this study was to investigate the annual transitions of MRSA strains with the CA-MRSA feature, which were identified as SCCmec type IV or V, in a hospital setting in Japan. Between 2005 and 2012, MRSA strains were collected from a tertiary-care hospital in Tokyo, Japan, and SCCmec typing, detection of the virulence factors and antimicrobial susceptibility testing were conducted. The rate of detection of type II SCCmec, which is found mainly in healthcare-associated MRSA, significantly decreased from 90.0 (2005–2006) to 74.3 % (2011–2012) (P < 0.01). In contrast, the rate of detection of type IV SCCmec, which is mainly found in CA-MRSA, significantly increased from 5.8 (2005–2006) to 16.3 % (2011–2012) (P < 0.01). The rate of detection of the toxic shock syndrome toxin-1 gene significantly decreased from 66.7 (2005–2006) to 51.6 % (2011–2012) (P < 0.01), whilst that of the Panton-Valentine leukocidin gene significantly increased from 0.1 (2005–2006) to 2.1 % (2011–2012) (P < 0.01). The resistance rates of cefotaxime, levofloxacin, clarithromycin and minocycline decreased every year. The resistance rates of these antimicrobial agents for the SCCmec type IV or V strains were significantly lower than those for the SCCmec type I or II strains (P < 0.01, respectively). Therefore, these results suggest that the annual transitions of the virulence factors and antibiograms in MRSA are closely related to the increase of SCCmec type IV/V strains.
Gordon L Archer - One of the best experts on this subject based on the ideXlab platform.
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gene acquisition at the insertion site for SCCmec the genomic island conferring methicillin resistance in staphylococcus aureus
Journal of Bacteriology, 2008Co-Authors: Michael J Noto, Barry N Kreiswirth, Alastair B Monk, Gordon L ArcherAbstract:Staphylococcus aureus becomes resistant to methicillin by acquiring a genomic island, known as staphylococcal chromosome cassette mec (SCCmec), which contains the methicillin resistance determinant, mecA. SCCmec is site-specifically integrated into the staphylococcal chromosome at a locus known as the SCCmec attachment site (attB). In an effort to gain a better understanding of the potential that methicillin-sensitive S. aureus (MSSA) isolates have for acquiring SCCmec, the nucleotide sequences of attB and surrounding DNA regions were examined in a diverse collection of 42 MSSA isolates. The chromosomal region surrounding attB varied among the isolates studied and appears to be a common insertion point for acquired foreign DNA. Insertions of up to 15.1 kb were found containing open reading frames with homology to enterotoxin genes, restriction-modification systems, transposases, and several sequences that have not been previously described in staphylococci. Two groups, containing eight and four isolates, had sequences found in known SCCmec elements, suggesting SCCmec elements may have evolved through repeated DNA insertions at this locus. In addition, the attB sequences of the majority of MSSA isolates in this collection differ from the attB sequences of strains for which integrase-mediated SCCmec insertion or excision has been demonstrated, suggesting that some S. aureus isolates may lack the ability to site-specifically integrate SCCmec into their chromosomes.
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related clones containing SCCmec type iv predominate among clinically significant staphylococcus epidermidis isolates
Antimicrobial Agents and Chemotherapy, 2003Co-Authors: Hilmar Wisplinghoff, Mark C Enright, Adriana E Rosato, Michael J Noto, William Craig, Gordon L ArcherAbstract:SCCmec is a mobile genetic element that carries the gene (mecA) mediating methicillin resistance in staphylococci. For Staphylococcus aureus, four SCCmec types have been described, one (type IV) of which has been associated with newly identified community-acquired methicillin-resistant S. aureus. However, the distribution of SCCmec types among S. epidermidis is not known. SCCmec typing of a collection of 44 methicillin-resistant Staphylococcus epidermidis (MRSE) isolates recovered between 1973 and 1983 from the blood of patients with prosthetic valve endocarditis (PVE) was performed by PCR amplification of key genetic elements (mecA, mecI, IS1272, and ccrAB). Of the 44 isolates, 1 (2%) harbored SCCmec type I, 15 (34%) harbored type II, 12 (28%) harbored type III, and 16 (36%) harbored type IV. The complete nucleotide sequence of SCCmec type IV was determined for 16 isolates and found to be identical in size (24 kb) and 98% homologous to DNA sequences published for S. aureus. Type IV SCCmec was also common (5 of 10 isolates) among a geographically dispersed collection of 10 recent (1998 to 2001) S. epidermidis bloodstream isolates. Multilocus sequence typing (MLST) (using the same seven genes presently employed for S. aureus MLST) of these MRSE isolates and of 10 additional recent geographically dispersed methicillin-susceptible isolates demonstrated that all 16 PVE isolates and 2 of 5 recent isolates harboring type IV SCCmec were in three related clonal groups. All three MSSE PVE isolates recovered from patients between 1976 and 1979 were in the same clonal groups as type IV SCCmec MRSE isolates. These data support the hypothesis of intra- and interspecies transfer of type IV SCCmec and suggest that there are clonal associations in S. epidermidis that correlate with SCCmec type.
Hidemasa Nakaminami - One of the best experts on this subject based on the ideXlab platform.
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Characterization of SCCmec type IV methicillin-resistant Staphylococcus aureus clones increased in Japanese hospitals
Journal of Medical Microbiology, 2018Co-Authors: Hidemasa Nakaminami, Shunsuke Takadama, Ayumu Ito, Mariko Hasegawa, Chika Jono, Miyuki Noguchi, Manami Shoshi, Takeaki Wajima, Takeshi Fujii, Hiroshi MaruyamaAbstract:Recently, the prevalence of staphylococcal cassette chromosome mec (SCCmec) type IV isolates, which are the major community-acquired methicillin-resistant Staphylococcus aureus (MRSA), have increased in Japanese hospitals. The aim of this study was to elucidate the detailed molecular epidemiological features of the SCCmec type IV clones in Japanese hospitals. When 2589 MRSA isolated from four hospitals in Tokyo, Japan between 2010 and 2014 were analysed, the proportion of SCCmec type IV overtook that of type II, which was the major type of hospital-acquired MRSA in 2014. Multilocus sequence typing showed that CC1 was the most predominant clone in the SCCmec type IV isolates. The clinical departments that the patients belonged to, pulsed-field gel electrophoresis analysis and antimicrobial susceptibility profiles suggested that the origin of the CC1-SCCmec type IV (CC1-IV) clone was a community setting. Our data show that the CC1-IV clone is becoming a predominant MRSA clone in Japanese hospitals.
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increase in SCCmec type iv strains affects trends in antibiograms of meticillin resistant staphylococcus aureus at a tertiary care hospital
Journal of Medical Microbiology, 2015Co-Authors: Ayumu Ito, Hidemasa Nakaminami, Takeshi Fujii, Kenta Utsumi, Norihisa NoguchiAbstract:The prevalence of community-acquired meticillin-resistant Staphylococcus aureus (CA-MRSA) strains has become a serious problem worldwide. The aim of this study was to investigate the annual transitions of MRSA strains with the CA-MRSA feature, which were identified as SCCmec type IV or V, in a hospital setting in Japan. Between 2005 and 2012, MRSA strains were collected from a tertiary-care hospital in Tokyo, Japan, and SCCmec typing, detection of the virulence factors and antimicrobial susceptibility testing were conducted. The rate of detection of type II SCCmec, which is found mainly in healthcare-associated MRSA, significantly decreased from 90.0 (2005–2006) to 74.3 % (2011–2012) (P < 0.01). In contrast, the rate of detection of type IV SCCmec, which is mainly found in CA-MRSA, significantly increased from 5.8 (2005–2006) to 16.3 % (2011–2012) (P < 0.01). The rate of detection of the toxic shock syndrome toxin-1 gene significantly decreased from 66.7 (2005–2006) to 51.6 % (2011–2012) (P < 0.01), whilst that of the Panton-Valentine leukocidin gene significantly increased from 0.1 (2005–2006) to 2.1 % (2011–2012) (P < 0.01). The resistance rates of cefotaxime, levofloxacin, clarithromycin and minocycline decreased every year. The resistance rates of these antimicrobial agents for the SCCmec type IV or V strains were significantly lower than those for the SCCmec type I or II strains (P < 0.01, respectively). Therefore, these results suggest that the annual transitions of the virulence factors and antibiograms in MRSA are closely related to the increase of SCCmec type IV/V strains.
