ABSTRACT
BACKGROUND Hepatitis C virus infection is probably the most common chronic viral infection and affects an estimated 180 million people worldwide. Extrahepatic manifestations are well recognized among patients with chronic HCV infection. CASE REPORT We report a case of melena occurring in a 69-year-old Japanese man who had been diagnosed with CHC and who was treated with antiviral therapy. CONCLUSIONS Finally, he was diagnosed with multiple small intestine ulcers in a short time. We herein report the case of HCV with rapidly developing small intestine ulcers.
Subject(s)
Duodenal Ulcer/diagnosis , Gastrointestinal Hemorrhage/diagnosis , Hepatitis C, Chronic/complications , Lymphoma, Non-Hodgkin/diagnosis , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antiviral Agents/therapeutic use , Biopsy, Needle , Colonoscopy/methods , Disease Progression , Duodenal Ulcer/drug therapy , Duodenal Ulcer/etiology , Duodenal Ulcer/pathology , Fatal Outcome , Gastrointestinal Hemorrhage/etiology , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/drug therapy , Humans , Immunohistochemistry , Lymphoma, Non-Hodgkin/drug therapy , Lymphoma, Non-Hodgkin/etiology , MaleABSTRACT
A bacterial insertion sequence (IS) is a mobile DNA sequence carrying only the transposase gene (tnp) that acts as a mutator to disrupt genes, alter gene expressions, and cause genomic rearrangements. "Canonical" ISs have historically been characterized by their terminal inverted repeats (IRs), which may form a stem-loop structure, and duplications of a short (non-IR) target sequence at both ends, called target site duplications (TSDs). The IS distributions and virulence potentials of Staphylococcus aureus genomes in familial infection cases are unclear. Here, we determined the complete circular genome sequences of familial strains from a Panton-Valentine leukocidin (PVL)-positive ST50/agr4 S. aureus (GN) infection of a 4-year old boy with skin abscesses. The genomes of the patient strain (GN1) and parent strain (GN3) were rich for "canonical" IS1272 with terminal IRs, both having 13 commonly-existing copies (ce-IS1272). Moreover, GN1 had a newly-inserted IS1272 (ni-IS1272) on the PVL-converting prophage, while GN3 had two copies of ni-IS1272 within the DNA helicase gene and near rot. The GN3 genome also had a small deletion. The targets of ni-IS1272 transposition were IR structures, in contrast with previous "canonical" ISs. There were no TSDs. Based on a database search, the targets for ce-IS1272 were IRs or "non-IRs". IS1272 included a larger structure with tandem duplications of the left (IRL) side sequence; tnp included minor cases of a long fusion form and truncated form. One ce-IS1272 was associated with the segments responsible for immune evasion and drug resistance. Regarding virulence, GN1 expressed cytolytic peptides (phenol-soluble modulin α and δ-hemolysin) and PVL more strongly than some other familial strains. These results suggest that IS1272 transposes through an IR-replacing mechanism, with an irreversible process unlike that of "canonical" transpositions, resulting in genomic variations, and that, among the familial strains, the patient strain has strong virulence potential based on community-associated virulence factors.
Subject(s)
DNA Transposable Elements/genetics , Genomics , Inverted Repeat Sequences/genetics , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics , Staphylococcus aureus/isolation & purification , Bacterial Toxins/chemistry , Bacterial Toxins/genetics , Base Sequence , Child, Preschool , Chromosome Mapping , Cluster Analysis , DNA, Circular/genetics , Exotoxins/chemistry , Exotoxins/genetics , Family , Female , Gene Duplication , Gene Expression Regulation, Bacterial , Genes, Bacterial , Genome, Bacterial , Humans , Leukocidins/chemistry , Leukocidins/genetics , Male , Mutagenesis, Insertional/genetics , Polymerase Chain Reaction , Prophages/physiology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sequence Analysis, DNA , Staphylococcal Infections/transmission , Staphylococcus aureus/pathogenicity , Virulence Factors/biosynthesis , Virulence Factors/geneticsABSTRACT
Streptococcus pneumoniae, a common human pathogen, colonizes the nasopharynx and causes diseases including acute otitis media (AOM). Herein, pneumococcal serotype distributions in children before and after PCV7 vaccination and in patients with pneumococcal disease in Siberian Russia (Krasnoyarsk) are reported. Analyses included antimicrobial susceptibility testing, sequence typing (ST), pulsed field gel electrophoresis, virulence-related surface protein gene (VSG) typing with novel primers and structural analysis by scanning electron microscopy. In healthy children (HC) prior to administration of PCV7, drug-susceptible serotype23F/ST1500 was a major pneumococcal genotype. In the PCV7 trial, multidrug-resistant serotype19A/ST320 emerged in vaccinees after PCV7, exhibiting a PCV7-induced serotype replacement. Multidrug-resistant serotype19A/ST320 was evident in patients with AOM. Community-acquired pneumonia (CAP) isolates showed genetic similarities to the AOM (ST320) genotype, constituting a common non-invasive AOM-CAP group. In contrast, meningitis isolates were more divergent. Overall, 25 ST types were identified; five (20%) of which were Krasnoyarsk-native. Regarding VSGs, PI-1 (rlrA/rrgB), PI-2 (pitA/B), psrP and cbpA were present at 54.3%, 38.6%, 48.6%, and 95.7%, respectively, with two major VSG content types, PI-1- /PI-2- /psrP+ /cbpA+ and PI-1+ /PI-2+ /psrP- /cbpA+ , being found for HC and non-invasive diseases, respectively. A major clone of serotype19A/ST320 (PI-1+ /PI-2+ ) produced the longest pneumococcal wire (pilus) structures in colonies. ST1016 (PI-1- /PI-2- ) in HC had HEp-2 cell-adherent pili. These results suggest that serotype19A/ST320 and related genotypes, with the VSG content type PI-1+ /PI-2+ /psrP- /cbpA+ , emerged in vaccinees after PCV7 in Siberia, accompanying diseases in non-vaccinated children, and that some genotypes (serotypes19A/ST320 and 18/ST1016) produced novel pneumococcal structures, predicting their roles in colony formation and adherence.
Subject(s)
Fimbriae, Bacterial/ultrastructure , Heptavalent Pneumococcal Conjugate Vaccine/immunology , Otitis Media/epidemiology , Pneumococcal Infections/epidemiology , Streptococcus pneumoniae/classification , Bacterial Adhesion/physiology , Cell Line , Child, Preschool , Humans , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Multilocus Sequence Typing , Otitis Media/microbiology , Otitis Media/prevention & control , Pneumococcal Infections/microbiology , Pneumococcal Infections/prevention & control , Russia/epidemiology , Siberia/epidemiology , Streptococcus pneumoniae/genetics , Streptococcus pneumoniae/immunology , Vaccination , Virulence Factors/geneticsABSTRACT
ST8/SCCmecIV community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has been a common threat, with large USA300 epidemics in the United States. The global geographical structure of ST8/SCCmecIV has not yet been fully elucidated. We herein determined the complete circular genome sequence of ST8/SCCmecIVc strain OC8 from Siberian Russia. We found that 36.0% of the genome was inverted relative to USA300. Two IS256, oppositely oriented, at IS256-enriched hot spots were implicated with the one-megabase genomic inversion (MbIN) and vSaß split. The behavior of IS256 was flexible: its insertion site (att) sequences on the genome and junction sequences of extrachromosomal circular DNA were all divergent, albeit with fixed sizes. A similar multi-IS256 system was detected, even in prevalent ST239 healthcare-associated MRSA in Russia, suggesting IS256's strong transmission potential and advantage in evolution. Regarding epidemiology, all ST8/SCCmecIVc strains from European, Siberian, and Far Eastern Russia, examined had MbIN, and geographical expansion accompanied divergent spa types and resistance to fluoroquinolones, chloramphenicol, and often rifampicin. Russia ST8/SCCmecIVc has been associated with life-threatening infections such as pneumonia and sepsis in both community and hospital settings. Regarding virulence, the OC8 genome carried a series of toxin and immune evasion genes, a truncated giant surface protein gene, and IS256 insertion adjacent to a pan-regulatory gene. These results suggest that unique single ST8/spa1(t008)/SCCmecIVc CA-MRSA (clade, Russia ST8-IVc) emerged in Russia, and this was followed by large geographical expansion, with MbIN as an epidemiological marker, and fluoroquinolone resistance, multiple virulence factors, and possibly a multi-IS256 system as selective advantages.
Subject(s)
Community-Acquired Infections/microbiology , Genome, Bacterial , Methicillin-Resistant Staphylococcus aureus/genetics , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Base Sequence , Biological Evolution , Community-Acquired Infections/pathology , DNA, Bacterial/chemistry , DNA, Bacterial/metabolism , DNA, Circular/chemistry , DNA, Circular/metabolism , Electrophoresis, Gel, Pulsed-Field , Erythromycin/pharmacology , Genotype , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/physiology , Microbial Sensitivity Tests , Molecular Sequence Data , RNA, Messenger/metabolism , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 16S/metabolism , Russia , Sequence Analysis, DNA , Sequence Inversion , Virulence/geneticsABSTRACT
Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a major concern worldwide. In the United States, ST8 CA-MRSA with SCCmecIVa (USA300) has been predominant, affecting the entire United States. In this study, we investigated Japanese ST8 CA-MRSA with new SCCmecIV1 (designated ST8 CA-MRSA/J), which has emerged in Japan since 2003. Regarding community spread and infections, ST8 CA-MRSA/J spread in 16.2-34.4% as a major genotype in the community in Japan, and was associated with skin and soft tissue infections (SSTIs), colitis, and invasive infections (sepsis, epidural abscesses, and necrotizing pneumonia), including influenza prodrome cases and athlete infections, similar to USA300. It spread to even public transport and Hong Kong through a Japanese family. Regarding genetic diversity, ST8 CA-MRSA/J included ST and spa variants and was classified into at least three pulsed-field gel electrophoresis types, ST8 Jα to γ. Of those, ST8 Jß was associated with severe invasive infections. As for genomics, ST8 CA-MRSA/J showed high similarities to USA300, but with marked diversity in accessory genes; e.g., ST8 CA-MRSA/J possessed enhanced cytolytic peptide genes of CA-MRSA, but lacked the Panton-Valentine leukocidin phage and arginine catabolic mobile element, unlike USA300. The unique features of ST8 CA-MRSA/J included a novel mosaic SaPI (designated SaPIj50) carrying the toxic shock syndrome toxin-1 gene with high expression; the evolution included salvage (through recombination) of hospital-acquired MRSA virulence. The data suggest that ST8 CA-MRSA/J has become a successful native clone in Japan, in association with not only SSTIs but also severe invasive infections (posing a threat), requiring attention.
Subject(s)
Genome, Bacterial , Methicillin-Resistant Staphylococcus aureus/genetics , Staphylococcal Infections , Gene Expression Regulation, Bacterial , Genomics , Genotype , Humans , Japan , Methicillin-Resistant Staphylococcus aureus/pathogenicity , Phylogeny , RNA, Messenger/genetics , VirulenceABSTRACT
Methicillin-resistant Staphylococcus aureus (MRSA) is a common multidrug-resistant (MDR) pathogen. We herein discussed MRSA and its infections in Krasnoyarsk, Siberian Russia between 2007 and 2011. The incidence of MRSA in 3,662 subjects was 22.0% and 2.9% for healthcare- and community-associated MRSA (HA- and CA-MRSA), respectively. The 15-day mortality rates for MRSA hospital- and community-acquired pneumonia (HAP and CAP) were 6.5% and 50%, respectively. MRSA CAP cases included pediatric deaths; of the MRSA pneumonia episodes available, ≥27.3% were associated with bacteremia. Most cases of HA-MRSA examined exhibited ST239/spa3(t037)/SCCmecIII.1.1.2 (designated as ST239Kras), while all CA-MRSA cases examined were ST8/spa1(t008)/SCCmecIV.3.1.1(IVc) (designated as ST8Kras). ST239Kras and ST8Kras strongly expressed cytolytic peptide (phenol-soluble modulin α, PSMα; and δ-hemolysin, Hld) genes, similar to CA-MRSA. ST239Kras pneumonia may have been attributed to a unique set of multiple virulence factors (MVFs): toxic shock syndrome toxin-1 (TSST-1), elevated PSMα/Hld expression, α-hemolysin, the staphylococcal enterotoxin SEK/SEQ, the immune evasion factor SCIN/SAK, and collagen adhesin. Regarding ST8Kras, SEA was included in MVFs, some of which were common to ST239Kras. The ST239Kras (strain OC3) genome contained: a completely unique phage, φSa7-like (W), with no att repetition; S. aureus pathogenicity island SaPI2R, the first TSST-1 gene-positive (tst+) SaPI in the ST239 lineage; and a super copy of IS256 (≥22 copies/genome). ST239Kras carried the Brazilian SCCmecIII.1.1.2 and United Kingdom-type tst. ST239Kras and ST8Kras were MDR, with the same levofloxacin resistance mutations; small, but transmissible chloramphenicol resistance plasmids spread widely enough to not be ignored. These results suggest that novel MDR and MVF+ HA- and CA-MRSA (ST239Kras and ST8Kras) emerged in Siberian Russia (Krasnoyarsk) associated with fatal pneumonia, and also with ST239Kras, a new (Siberian Russian) clade of the ST239 lineage, which was created through stepwise evolution during its potential transmission route of Brazil-Europe-Russia/Krasnoyarsk, thereby selective advantages from unique MVFs and the MDR.
Subject(s)
Community-Acquired Infections/microbiology , Evolution, Molecular , Genome, Bacterial , Methicillin-Resistant Staphylococcus aureus/genetics , Pneumonia/microbiology , Staphylococcal Infections/microbiology , Virulence Factors/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Child , Child, Preschool , Community-Acquired Infections/mortality , Community-Acquired Infections/pathology , DNA, Bacterial/analysis , Drug Resistance, Multiple, Bacterial , Female , Follow-Up Studies , Genotype , Humans , Infant , Infant, Newborn , Male , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Middle Aged , Plasmids/analysis , Plasmids/genetics , Pneumonia/mortality , Pneumonia/pathology , Retrospective Studies , Russia , Staphylococcal Infections/mortality , Staphylococcal Infections/pathology , Survival Analysis , Young AdultABSTRACT
An 89-year-old man suffered from and died of necrotizing pneumonia with rapid progression and cavity formation due to methicillin-resistant Staphylococcus aureus (MRSA). He was at no risk for hospital-acquired MRSA infection. His MRSA exhibited genotype ST5/spa2(t002)/agr2/SCCmecII/coagulaseII and was negative for Panton-Valentine leukocidin, indicating the New York/Japan clone (the predominant epidemic hospital-acquired MRSA clone in Japan). However, this strain expressed the cytolytic peptide (phenol-soluble modulin or δ-hemolysin) genes at high level, similar to USA300 (the most common community-acquired MRSA in the United States), indicating a variant of the New York/Japan clone with an important feature of community-acquired MRSA.
Subject(s)
Community-Acquired Infections/diagnosis , Community-Acquired Infections/microbiology , Methicillin-Resistant Staphylococcus aureus/classification , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Pneumonia, Staphylococcal/diagnosis , Pneumonia, Staphylococcal/microbiology , Aged , Aged, 80 and over , Bacterial Proteins/genetics , Bacterial Toxins/genetics , Exotoxins/genetics , Genotype , Hemolysin Proteins/genetics , Humans , Japan , Leukocidins/genetics , Male , Methicillin-Resistant Staphylococcus aureus/genetics , Virulence Factors/geneticsABSTRACT
A 15-year-old boy, who had had a furuncle on his femur, developed femoral pyomyositis and osteomyelitis complicated by septic pulmonary embolism. Panton-Valentine leukocidin-positive (PVL(+)) ST59 methicillin-susceptible Staphylococcus aureus (MSSA) was isolated from pus and blood. Chemotherapy was started with cefazolin, followed by combination therapy with meropenem/vancomycin with surgery. The MSSA (strain KS1) was positive for increased levels of cytolytic peptide (psmα and hld) and staphylococcal enterotoxin B (SEB), and manifested IS1216V-mediated multidrug resistance (to erythromycin, clindamycin, kanamycin, streptomycin, and chloramphenicol), similar to a genome-analyzed reference strain (PM1) of ST59/SCCmecV(5C2&5) community-associated methicillin-resistant S. aureus (Taiwan CA-MRSA), but unlike another reference strain (M013) of Taiwan CA-MRSA in terms of resistance. The data suggest that CA-MSSA KS1, characterized by PVL, increased levels of cytolytic peptide, SEB, and multidrug resistance, is a possible ancestral strain of Taiwan CA-MRSA and causes the unique association of osteomyelitis and septic pulmonary embolism, requiring complicated management.
Subject(s)
Bacterial Toxins/metabolism , Community-Acquired Infections/microbiology , Exotoxins/genetics , Leukocidins/genetics , Osteomyelitis/microbiology , Pulmonary Embolism/etiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/isolation & purification , Adolescent , Anti-Bacterial Agents/therapeutic use , Bacterial Toxins/genetics , Community-Acquired Infections/complications , Community-Acquired Infections/drug therapy , Community-Acquired Infections/surgery , Debridement , Genotype , Humans , Male , Molecular Typing , Osteomyelitis/complications , Osteomyelitis/drug therapy , Osteomyelitis/surgery , Pulmonary Embolism/drug therapy , Staphylococcal Infections/complications , Staphylococcal Infections/drug therapy , Staphylococcal Infections/surgery , Staphylococcus aureus/classification , Staphylococcus aureus/genetics , Staphylococcus aureus/metabolism , TaiwanABSTRACT
Staphylococcus aureus has occupied an important position in public health as a cause of food poisoning and hospital-acquired MRSA (HA-MRSA) infections. The spread of community-acquired MRSA (CA-MRSA) infections has also recently become a concern. However, the sources of this infection remain unclear, and there are few reports of epidemiology information. In order to understand MRSA spread in the community, we investigated the distribution of MRSA strains in commercially distributed raw meat samples (n=305) and stool samples from outpatients with diarrhea (n=1,543) from the same meat distribution region in Oita Prefecture, Japan. 301 Staphylococcus aureus strains were isolated and 18 of them were MRSA (2 from chicken meat, 1 from duck meat, 1 from pork meat, and 14 from patients with diarrhea). All 18 MRSA strains were negative for Panton-Valentine leucocidin gene. In this study conducting a comparison of properties and a molecular epidemiological analysis of MRSA isolated from commercially distributed meat and diarrhea patient stools, the results suggest that commercially distributed meat could play a role in the prevalence of CA-MRSA in the community.
Subject(s)
Food Microbiology , Meat/microbiology , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Staphylococcal Infections/microbiology , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Food Analysis , Humans , Staphylococcal Infections/epidemiologyABSTRACT
The ST5 lineage of methicillin-resistant Staphylococcus aureus (MRSA) is one of the most globally disseminated hospital-associated MRSA (HA-MRSA) lineages. We isolated a new local variant (designated ST764) over at least 5 years that causes invasive infections, including necrotizing fasciitis, and is carried by medical students, as well as household members. Analysis of the genome sequence of one isolate compared to that of the reference ST5 strain revealed that ST764 had acquired virulence traits similar to those of community-associated MRSA (CA-MRSA) through the acquisition of two new mobile genetic elements, ACMEII and SaPInn54, which carried ACME arcA and the staphylococcal enterotoxin B gene (seb), respectively, and through enhanced expression of cytolytic peptide genes, although ST764 was negative for Panton-Valentine leukocidin. Other differences between ST764 and ST5 included the acquisition of an ACMEII-related cassette (cJR1), prophage φ2NN54, and streptococcal Tn5251 and decreased numbers of copies of Tn554. As for superantigen genes, although the two possessed seg, sei, sem, sen, and seo, ST764 lacked tst, sec, sel, and sep. The data suggest that ST764 MRSA is a novel hybrid variant of ST5 HA-MRSA with the characteristics of CA-MRSA and that the evolution of ST764 includes multiple steps, e.g., acquisition of novel or nonstaphylococcal mobile elements.
Subject(s)
Bacterial Proteins/genetics , Methicillin-Resistant Staphylococcus aureus/genetics , Virulence/physiology , Enterotoxins/genetics , Genome, Bacterial/genetics , Methicillin-Resistant Staphylococcus aureus/pathogenicity , Virulence/geneticsABSTRACT
Enterobacteriaceae, carrying the New Delhi metallo-ß-lactamase-1 (NDM-1) gene (bla (NDM-1)), have emerged and posed a threat since 2006. In Japan, bla (NDM-1)-carrying Escherichia coli was first described in 2010. In this study, we characterized NDM-1-positive Klebsiella pneumoniae strain 419 in Japan, which was isolated from the urine of a 90-year-old Japanese patient who had never been to the Indian subcontinent. K. pneumoniae 419 belonged to ST42. It possessed a surface capsule (with untypeable capsular PCR types) and was resistant to serum killing. K. pneumoniae 419 cells were occasionally flagellated or piliated and autoaggregated. K. pneumoniae 419 was resistant to ß-lactams (including carbapenems), aminoglycosides, and fluoroquinolones, and was susceptible to imipenem (or biapenem), aztreonam, polymixin B, and colistin. It possessed at least eight plasmids; of those, a 74-kb plasmid (pKPJ1) of the replicon FIIA carried bla (NDM-1) and was conjugally transferred to E. coli strains, with a 71-kb transferable azithromycin-resistant (mphA (+)) plasmid of the replicon F (pKPJ2), as a large (145-kb) plasmid (pKPJF100) through a transposition event. In addition to bla (NDM-1), pKPJ1 carried arr-2, pKPJ2 carried mphA, and pKPJF100 carried both. They were negative for the 16S rRNA methylase gene, e.g., which is frequently associated with bla (NDM-1). The data demonstrate that K. pneumoniae 419 possessed virulence- and fitness-associated surface structures, was resistant to serum killing, and possessed a unique (or rare) genetic background in terms of ST type and bla (NDM-1)-carrying plasmid.
Subject(s)
Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/ultrastructure , Plasmids/genetics , beta-Lactamases/biosynthesis , Adult , Anti-Bacterial Agents/pharmacology , Azithromycin/pharmacology , Blood Bactericidal Activity , Conjugation, Genetic , Drug Resistance, Bacterial/genetics , Drug Resistance, Multiple, Bacterial/genetics , Humans , Japan/epidemiology , Klebsiella Infections/epidemiology , Klebsiella Infections/microbiology , Klebsiella pneumoniae/isolation & purification , Microbial Sensitivity Tests , Microscopy, Electron , Urinary Tract Infections/microbiology , Urine/microbiology , beta-Lactam Resistance , beta-Lactamases/geneticsABSTRACT
Similarly to Helicobacter pylori but unlike Vibrio cholerae O1/O139, Campylobacter jejuni is non-motile at 20°C but highly motile at ≥37°C. The bacterium C. jejuni has one of the highest swimming speeds reported (>100 µm/s), especially at 42°C. Straight and spiral bacterial shapes share the same motility. C. jejuni has a unique structure in the flagellate polar region, which is characterized by a cup-like structure (beneath the inner membrane), a funnel shape (opening onto the polar surface) and less dense space (cytoplasm). Other Campylobacter species (coli, fetus, and lari) have similar motility and flagellate polar structures, albeit with slight differences. This is especially true for Campylobacter fetus, which has a flagellum only at one pole and a cup-like structure composed of two membranes.
Subject(s)
Campylobacter/physiology , Campylobacter/ultrastructure , Flagella/ultrastructure , Locomotion , Campylobacter/classification , Campylobacter/isolation & purification , Campylobacter Infections/microbiology , Humans , Microscopy, Electron, Scanning , Microscopy, Electron, TransmissionABSTRACT
Methicillin-resistant Staphylococcus aureus (MRSA) with ST59/SCCmecV and Panton-Valentine leukocidin gene is a major community-acquired MRSA (CA-MRSA) lineage in Taiwan and has been multidrug-resistant since its initial isolation. In this study, we studied the acquisition mechanism of multidrug resistance in an ST59 CA-MRSA strain (PM1) by comparative genomics. PM1's non-ß-lactam resistance was encoded by two unique genetic traits. One was a 21,832-bp composite mobile element structure (MES(PM1)), which was flanked by direct repeats of enterococcal IS1216V and was inserted into the chromosomal sasK gene; the target sequence (att) was 8 bp long and was duplicated at both ends of MES(PM1). MES(PM1) consisted of two regions: the 5'-end side 12.4-kb region carrying Tn551 (with ermB) and Tn5405-like (with aph[3']-IIIa and aadE), similar to an Enterococcus faecalis plasmid, and the 3'-end side 6,587-bp region (MES(cat)) that carries cat and is flanked by inverted repeats of IS1216V. MES(cat) possessed att duplication at both ends and additional two copies of IS1216V inside. MES(PM1) represents the first enterococcal IS1216V-mediated composite transposon emerged in MRSA. IS1216V-mediated deletion likely occurred in IS1216V-rich MES(PM1), resulting in distinct resistance patterns in PM1-derivative strains. Another structure was a 6,025-bp tet-carrying element (MES(tet)) on a 25,961-bp novel mosaic penicillinase plasmid (pPM1); MES(tet) was flanked by direct repeats of IS431, but with no target sequence repeats. Moreover, the PM1 genome was deficient in a copy of the restriction and modification genes (hsdM and hsdS), which might have contributed to the acquisition of enterococcal multidrug resistance.
Subject(s)
Drug Resistance, Multiple, Bacterial/genetics , Interspersed Repetitive Sequences , Methicillin-Resistant Staphylococcus aureus/genetics , Staphylococcal Infections/microbiology , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Toxins/genetics , Chromosomes, Bacterial , Community-Acquired Infections/microbiology , DNA Restriction-Modification Enzymes/genetics , Drug Resistance, Multiple, Bacterial/drug effects , Enterococcus faecalis/genetics , Exotoxins/genetics , Genome, Bacterial , Genomics/methods , Humans , Leukocidins/genetics , Microbial Sensitivity Tests , Molecular Sequence Data , Taiwan , Tetracycline/pharmacology , beta-Lactams/pharmacologyABSTRACT
Methicillin-resistant Staphylococcus aureus (MRSA) includes hospital-acquired MRSA (HAMRSA) and community-acquired MRSA (CA-MRSA). Panton-Valentine leukocidin (PVL)-positive multilocus sequence type 30 (ST30) MRSA is one of worldwide CA-MRSA, which has also persisted in Japan since the 1980s. However, unexpectedly, it was not the same ST30 clone throughout. Before 2000, it was HA-MRSA with spa43 and ψSa3sea (phage Sa3 carrying the sea gene) and only one PVL-positive MRSA in Japan; in the 1980s, ST30 MRSA accounted for 23.5% of HA-MRSA, showed multidrug resistance, had high MICs for oxacillin and imipenem, and caused decubitus and pneumonia in hospitalized patients. A dynamic clonal change (spa43/ψSa3seaâ spa19) occurred around 2000-2002. A rare spa43/ψSa3sea/SCCmecI-IE25923 genotype also emerged. After 2002, the prevalent spa19 clone was CA-MRSA; it accounted for only 0.3% (or less) of MRSA in hospitals but 7.6% of CA-MRSA. Since 2007, PVL-positive CA-MRSA with other ST types (such as ST8, ST22, and ST59) also emerged in Japan, albeit at a low frequency. ST30/spa19 CA-MRSA occasionally caused severe invasive infections and a novel ST1335/spa19 genotype emerged. These ST30/spa19 CA-MRSA and variants were identified by pulsed field gel electrophoresis. Further analysis revealed that PVL-positive ST30/spa19 CA-MRSA is a highlyvirulent, successful clone, having a potential of clonal expansion.
Subject(s)
Bacterial Toxins/genetics , Evolution, Molecular , Exotoxins/genetics , Leukocidins/genetics , Methicillin-Resistant Staphylococcus aureus/genetics , Staphylococcal Infections/microbiology , Adolescent , Adult , Cell Line , Child , Child, Preschool , Drug Resistance, Multiple, Bacterial , Electrophoresis, Gel, Pulsed-Field , Female , Genes, Bacterial , Genetic Linkage , History, 20th Century , History, 21st Century , Host-Pathogen Interactions , Humans , Infant , Male , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/pathogenicity , Middle Aged , Phenotype , Phylogeny , Staphylococcal Infections/history , Transcription, Genetic , Virulence/geneticsABSTRACT
The effects of Lactobacillus johnsonii La1 (LC1) on Helicobacter pylori colonization in the stomach were investigated. H. pylori colonization and gastritis in LC1-inoculated Mongolian gerbils were significantly less intense than those in the control animals. LC1 culture supernatant (>10-kDa fraction) inhibited H. pylori motility and induced bacterial aggregation in human gastric epithelial cells, suggesting the potential of clinical use of LC1 product.
Subject(s)
Gastritis/drug therapy , Helicobacter Infections/drug therapy , Helicobacter pylori/drug effects , Lactobacillus/physiology , Probiotics/therapeutic use , Administration, Oral , Animals , Bacterial Adhesion/drug effects , Colony Count, Microbial , Disease Models, Animal , Gastric Mucosa/drug effects , Gastric Mucosa/microbiology , Gastritis/complications , Gastritis/microbiology , Gerbillinae , Helicobacter Infections/complications , Helicobacter Infections/microbiology , Helicobacter pylori/growth & development , Helicobacter pylori/pathogenicity , Humans , Male , Microbial Viability/drug effects , Probiotics/administration & dosage , Severity of Illness Index , Stomach/drug effects , Stomach/microbiologyABSTRACT
Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a major concern worldwide. In the United States, ST8 CA-MRSA with SCCmecIVa (USA300) has been predominant, affecting the entire United States. In this study, we investigated Japanese ST8 CA-MRSA with new SCCmecIVl (designated ST8 CA-MRSA/J), which has emerged in Japan since 2003. Regarding community spread and infections, ST8 CA-MRSA/J spread in 16.2-34.4% as a major genotype in the community in Japan, and was associated with skin and soft tissue infections (SSTIs), colitis, and invasive infections (sepsis, epidural abscesses, and necrotizing pneumonia), including influenza prodrome cases and athlete infections, similar to USA300. It spread to even public transport and Hong Kong through a Japanese family. Regarding genetic diversity, ST8 CA-MRSA/J included ST and spa variants and was classified into at least three pulsed-field gel electrophoresis types, ST8 Jα to γ. Of those, ST8 Jß was associated with severe invasive infections. As for genomics, ST8 CA-MRSA/J showed high similarities to USA300, but with marked diversity in accessory genes; e.g., ST8 CA-MRSA/J possessed enhanced cytolytic peptide genes of CA-MRSA, but lacked the Panton-Valentine leukocidin phage and arginine catabolic mobile element, unlike USA300. The unique features of ST8 CA-MRSA/J included a novel mosaic SaPI (designated SaPIj50) carrying the toxic shock syndrome toxin-1 gene with high expression; the evolution included salvage (through recombination) of hospital-acquired MRSA virulence. The data suggest that ST8 CA-MRSA/J has become a successful native clone in Japan, in association with not only SSTIs but also severe invasive infections (posing a threat), requiring attention.
Subject(s)
Communicable Diseases, Emerging/epidemiology , Community-Acquired Infections/epidemiology , Genetic Variation , Genomics , Methicillin-Resistant Staphylococcus aureus/genetics , Staphylococcal Infections/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Child , Child, Preschool , Communicable Diseases, Emerging/microbiology , Communicable Diseases, Emerging/transmission , Community-Acquired Infections/microbiology , Community-Acquired Infections/transmission , Female , Humans , Infant , Japan/epidemiology , Male , Methicillin-Resistant Staphylococcus aureus/classification , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Microbial Sensitivity Tests , Middle Aged , Molecular Epidemiology , Soft Tissue Infections , Staphylococcal Infections/microbiology , Staphylococcal Infections/transmission , Virulence Factors/genetics , Young AdultABSTRACT
The incidence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infection has been increasing; however, the sources of infection remain unclear. Therefore, we investigated the involvement of meat as a possible mediator of CA-MRSA infection. We examined the distribution of MRSA strains in commercially distributed raw meat samples (n = 197) and diarrheal stool samples of outpatients (n = 1,287) that were collected in Oita Prefecture, Japan, between 2003 and 2009 for routine legal inspections. Fourteen MRSA strains were isolated from three meat and 11 stool samples. Among these, seven isolates from three meat and four stool samples exhibited the same epidemiological marker profiles [coagulase type III, staphylococcal enterotoxin C, staphylococcal chromosomal cassette mec (SCCmec) type IV, ST8, spa type 606 (t1767), and toxic shock syndrome toxin-1 (TSST-1) producing type]. Furthermore, of the seven strains, three isolates from two meat samples and one stool sample collected in 2007 exhibited completely identical characteristics with respect to phage open reading frame (ORF) typing, pulsed-field gel electrophoresis, and drug susceptibility profiles. The results suggest that commercially distributed meat could play a role in the prevalence of CA-MRSA in the community.
Subject(s)
Community-Acquired Infections/transmission , Meat/microbiology , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Staphylococcal Infections/transmission , Bacterial Proteins/genetics , Bacterial Toxins/genetics , Cluster Analysis , Community-Acquired Infections/microbiology , Diarrhea/microbiology , Feces/microbiology , Genotype , Japan , Molecular Epidemiology , Molecular Typing , Staphylococcal Infections/microbiologyABSTRACT
Helicobacter pylori in Vladivostok, Far Eastern Russia, was investigated during 2004 to 2009. The genotype cagA(+) vacA(+) (s1/m1 or m2) accounted for 74.7%, with cagA(-) vacA(+) (s2/m2) at 11.2%. The CagA EPIYA type was mainly Western ABC, with minor types (ABCCC and novel AAABC) or non-Western/non-East Asia type (AB). Regarding drug resistance, metronidazole resistance was the highest, with a marked decrease in 6 years (from 71.4% to 30.8%); in contrast, levofloxacin and clarithromycin resistance increased. The data indicate that in Vladivostok, H. pylori was mainly the Western (not East Asian) type and dynamic changes in drug resistance occurred during 6 years.
Subject(s)
Drug Resistance, Bacterial , Helicobacter Infections/microbiology , Helicobacter pylori/drug effects , Helicobacter pylori/pathogenicity , Virulence Factors/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/pharmacology , Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Child , Asia, Eastern , Female , Genotype , Helicobacter pylori/isolation & purification , Humans , Male , Middle Aged , Russia , Virulence , Young AdultABSTRACT
Two distinct classes of methicillin-resistant Staphylococcus aureus (MRSA) are spreading in hospitals (as hospital-acquired MRSA, HA-MRSA) and in the community (as community-acquired MRSA, CA-MRSA). Multilocus sequence type (ST) 239 MRSA, one of the most worldwide-disseminated lineages, has been noted as a representative HA-MRSA. Here, we isolated ST239 MRSA (spa type 3 [t037] and staphylococcal cassette chromosome mec [SCCmec] type III.1.1.1) and its novel variant with ST239/spa351 (t030)/SCCmecIII.1.1.4 (SCCmecIII(R)) not only from hospitals but also from patients with urethritis in the community in Russia. The Russian variant (strain 16K) possessed a hybrid genome consisting of CC8 and CC30, similar to the ST239/spa3/SCCmecIII.1.1.1 HA-MRSA (TW20) genome, but with marked diversity. The 16K' CC30 section had SCCmecIII(R) carrying the dcs-carrying unit (which corresponded to the SCCmecIVc J3 joining region of ST30 CA-MRSA), lacked SCCmercury, and possessed a novel mobile element structure (MES16K) carrying the ccrC-carrying unit (with the recombinase gene ccrC1 allele 3) and drug resistance tranposons. The Russian variant included strains with a high ability to transfer its multiple drug resistance by conjugation; e.g., for strain 16K, the transfer frequency of a chloramphenicol resistance plasmid (p16K-1 with 2.9 kb in size) reached 1.4×10(-2), followed by Tn554 conjugative transfer at 3.6×l0(-4). The Russian variant, which has been increasing recently, included divergent strains with different plasmid patterns and pulsed field gel electrophoresis profiles. The data demonstrate the alternative nature of ST239 MRSA as CA-MRSA and also as a drug resistance disseminator, and its micro but dynamic evolution in Russia.
Subject(s)
Genome, Bacterial/genetics , Genomics/methods , Methicillin-Resistant Staphylococcus aureus/genetics , Russia , Sequence Analysis, DNAABSTRACT
Methicillin-resistant Staphylococcus aureus (MRSA) not only causes disease in hospitals, but also in the community. The characteristics of MRSA transmission in the environment remain uncertain. In this study, MRSA were isolated from public transport in Tokyo and Niigata, Japan. Of 349 trains examined, eight (2.3%) were positive for MRSA. The MRSA isolated belonged to sequence types (STs) 5, 8, 88, and 89, and included community infection-associated ST8 MRSA (with novel type IV staphylococcal cassette chromosome mec) and the ST5 New York/Japan hospital clone. The data indicate that public transport could contribute to the spread of community-acquired MRSA, and awareness of this mode of transmission is necessary.