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PubMed2026

Genomic Characterization of Antimicrobial Resistance and Virulence in ST11 Carbapenem-Resistant Klebsiella Pneumoniae Colonizing the Intestinal Tract of Elderly Inpatients.

BACKGROUND: This study aimed to elucidate the molecular epidemiology and virulence characteristics of ST11 carbapenem-resistant Klebsiella pneumoniae (CRKP) colonizing the intestinal tract of elderly inpatients in the Chongzhou region, providing a basis for controlling the transmission of such resistant bacteria in high-risk populations. METHODS: CRKP strains isolated from the intestines of elderly inpatients in this region between January 2023 and June 2024 were collected. ST11 strains were identified via multilocus sequence typing (MLST). Whole-genome sequencing, antimicrobial susceptibility testing, and string test, serum killing, biofilm formation, capsular polysaccharide quantification were employed to characterize their resistance genes, virulence genes, and molecular typing profiles. RESULTS: Among 58 CRKP isolates, 17 (29.3%) were ST11. ST11-KL64 was the dominant clone (70.6%). All isolates carried the carbapenemase gene bla KPC-2 and exhibited extensive drug resistance, with tigecycline retaining the highest susceptibility (64.7%). The yersiniabactin system genes (ybtS, fyuA, entB) were universally present, whereas the aerobactin gene cluster (iucABCD-iutA) was detected in only 17.6% of isolates. The virulence regulator rmpA2 was incomplete in all carriers. The hypermucoviscosity phenotype was observed in 35.3% of isolates, which correlated with serum resistance in some strains. Biofilm formation was variable. The mortality rate among colonized patients was 35.3%. CONCLUSION: The ST11-KL64 clone is dominant among CRKP strains colonizing the intestinal tract of elderly patients in this region. This clone universally carries the bla KPC-2 gene conferring carbapenem resistance and exhibits a unique virulence gene profile characterized by a low carriage rate of classical hypervirulence markers and an incomplete rmpA2 regulator gene. This finding clarifies the local epidemic status of this clone and underscores the importance of implementing active surveillance and targeted prevention strategies for high-risk populations.

KL64 serotype↗
PubMed2006

Virulence markers and genetic relationships of Shiga toxin-producing Escherichia coli strains from serogroup O111 isolated from cattle.

Shiga toxin-producing Escherichia coli (STEC) strains isolated from healthy cattle (O111:NM, seven strains; O111:H8, three strains) in Brazil were studied and compared to previously characterized human strains in regard to their phenotypic and genotypic characteristics to evaluate their pathogenic potential. Most bovine STEC O111 strains were isolated from dairy calves, and strains with genotypes stx1 alone and stx1/stx2 (variant stx2) occurred in different regions. Irrespective of the stx genotype, all strains were positive for eae theta, alpha variants of tir, espA and espB, and for ler, qseA, iha, astA and efa1 genes. Only one strain was negative for EHEC-hlyA and all strains were negative for iha, saa and espP genes and for EAF and bfpA, genetic markers of EPEC. Except for the presence of stx2, bovine strains showed the same profile of putative virulence genes found among the human strains. Similar biochemical behavior was identified among the strains analysed. Two bovine STEC strains produced the localized adherence (LA) phenotype in 6-h tests with Caco-2 (human enterocyte) cells. Intimate attachment (judged by the FAS test) was found in 9 out of 10 bovine strains as it was observed for the human STEC strains. RAPD-PCR analysis showed two distinct RAPD groups among the STEC O111 strains examined. Despite the relative low frequency of STEC O111 strains recovered from cattle no differences in their pathogenic potential were observed compared to some strains isolated from human diarrhea, suggesting that healthy cattle may be a potential source of infection for humans in Brazil.

Animals↗
PubMed1992

Characterization of the outer membrane proteins of Bordetella avium.

The outer membrane proteins of Bordetella avium were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Sarkosyl-insoluble outer membrane protein-enriched profiles from 50 virulent B. avium isolates, containing major 21,000- and 37,000-molecular-weight proteins (21K and 37K proteins, respectively) and at least 13 less intensely stained proteins with molecular weights ranging from 13,500 to 143,000, were very similar. The 21K, 27K, 31K, and 37K outer membrane proteins were shown to be associated noncovalently with the underlying peptidoglycan layer. It was necessary to treat cell envelopes with 2% sodium dodecyl sulfate and at temperatures in excess of 60 degrees C for 15 min to release these proteins. Exposure of proteins on the cell surface of B. avium was assessed by labeling with 125I followed by electrophoresis. As many as 13 bands were present in profiles from labeled whole cells. Of the surface-labeled bands, eight corresponded to bands in a radiolabeled outer membrane preparation. The outer membrane protein profile of B. avium was compared with profiles from other Bordetella spp., including 20 B. avium-like and 16 B. bronchiseptica strains isolated from turkeys. The outer membrane protein profile of B. avium was distinctly different from those of the other bordetella. The effect of variations in the growth medium on the expression of outer membrane proteins of B. avium was examined. Expression of 22K, 26K, 56K, and 73K proteins was decreased or eliminated by addition of 50 mM MgSO4 to the medium.

Bacterial Outer Membrane Proteins↗
PubMed2007

Proteomic identification and characterization of bacterial factors associated with Burkholderia cenocepacia survival in a murine host.

Burkholderia cenocepacia is a member of the Burkholderia cepacia complex, a diverse family of Gram-negative bacteria that are serious respiratory pathogens in immunocompromised patients and individuals with cystic fibrosis. To identify putative bacterial virulence determinants, proteomic profiles were compared between two B. cenocepacia isolates that demonstrated differential persistence in a mouse model of pulmonary infection; clinical isolate C1394 is rapidly cleared from the murine lung whereas the strain variant, C1394mp2, persists. Two-dimensional (2D) gel electrophoresis was used to identify candidate proteins involved in B. cenocepacia survival in a susceptible host. The 2D proteome of the persistent isolate (C1394mp2) revealed loss of an alkyl hydroperoxide reductase subunit C (AhpC) protein spot and increased production of flagellin proteins. Loss of AhpC expression in C1394mp2 correlated with enhanced susceptibility to oxidative stress. C1394mp2 expressed increased flagellin production and enhanced swimming motility, traits that were subject to regulation by heat and low pH. Together, these results revealed differential expression and stress regulation of putative virulence determinants associated with B. cenocepacia persistence in a susceptible host.

Animals↗
PubMed2003

Acanthamoeba sohi, n. sp., a pathogenic Korean isolate YM-4 from a freshwater fish.

A new species of Acanthamoeba was isolated from a freshwater fish in Korea and tentatively named Acanthamoeba sp. YM-4 (Korean isolate YM-4). The trophozoites were 11.0-23.0 micrometer in length and had hyaline filamentous projections. Cysts were similar to those of A. culbertsoni and A. royreba, which were previously designated as Acanthamoeba group III. Acanthamoeba YM-4 can survive at 40 degrees C, and its generation time was 19.6 hr, which was longer than that of A. culbertsoni. In terms of the in vitro cytotoxicity of lysates, Acanthamoeba YM-4 was weaker than A. culbertsoni, but stronger than A. polyphaga. On the basis of the mortality of experimentally infected mice, Acanthamoeba YM-4 was found to be highly virulent. The isoenzymes profile of Acanthamoeba YM-4 was similar to that of A. royreba. An anti-Acanthamoeba YM-4 monoclonal antibody, McAY7, was found to react only with Acanthamoeba YM-4, and not with A. culbertsoni. Random amplified polymorphic DNA marker analysis and RFLP analysis of mitochondrial DNA and of 18S small subunit ribosomal RNA, placed Acanthamoeba YM-4 in a separate cluster on the basis of phylogenetic distances. Thus the Acanthamoeba Korean isolate YM-4 was identified as a new species, and assigned as Acanthamoeba sohi.

Acanthamoeba↗
PubMed2004

Pathogenic free-living amoebae in Korea.

Acanthamoeba and Naegleria are widely distributed in fresh water, soil and dust throughout the world, and cause meningoencephalitis or keratoconjunctivitis in humans and other mammals. Korean isolates, namely, Naegleria sp. YM-1 and Acanthamoeba sp. YM-2, YM-3, YM-4, YM-5, YM-6 and YM-7, were collected from sewage, water puddles, a storage reservoir, the gills of a fresh water fish, and by corneal washing. These isolates were categorized into three groups based on the mortalities of infected mice namely, highly virulent (YM-4), moderately virulent (YM-2, YM-5 and YM-7) and nonpathogenic (YM-3). In addition, a new species of Acanthamoeba was isolated from a freshwater fish in Korea and tentatively named Korean isolate YM-4. The morphologic characters of its cysts were similar to those of A. culbertsoni and A. royreba, which were previously designated as Acanthamoeba group III. Based on experimentally infected mouse mortality, Acanthamoeba YM-4 was highly virulent. The isoenzymes profile of Acanthamoeba YM-4 was similar to that of A. royreba. Moreover, an anti-Acanthamoeba YM-4 monoclonal antibody reacted only with Acanthamoeba YM-4, and not with A. culbertsoni. Random amplified polymorphic DNA marker analysis and RFLP analysis of mitochondrial DNA and of a 18S small subunit ribosomal RNA, placed Acanthamoeba YM-4 in a separate cluster based on phylogenic distances. Thus Acanthamoeba YM-4 was identified as a new species, and assigned Acanthamoeba sohi. Up to the year 2002 in Korea, two clinical cases were found to be infected with Acanthamoeba spp. These patients died of meningoencephalitis. In addition, one case of Acanthamoeba pneumonia with an immunodeficient status was reported and Acanthamoeba was detected in several cases of chronic relapsing corneal ulcer, chronic conjunctivitis, and keratitis.

Acanthamoeba↗
PubMed1988

Virulence factors of lactose-negative Escherichia coli strains isolated from children with diarrhea in Somalia.

Lactose-negative Escherichia coli strains were isolated at high frequency from children with diarrhea in Somalia during a 2-year study on diarrheal diseases. Sixty-four of these strains, considered to be a representative sample, were characterized for virulence factors, plasmid profiles, and antibiotic resistance. Of these strains, 5 were recognized as enteroinvasive E. coli (they were serotyped as O135:K-:H-), 6 belonged to classical enteropathogenic E. coli serotypes, 9 were able to adhere to tissue culture cells (of these, 4 showed a pattern of localized adherence and 1 was an enteropathogenic strain), 18 were both adherent and hemolytic, and 8 were simply hemolytic. None hybridized with 32P-labeled heat-labile or heat-stable (a and b) enterotoxin gene probes or produced moderate or high-level cytotoxic effects on HeLa cells. Of the 64 strains examined, 24 produced mannose-resistant hemagglutination with human, chicken, and monkey erythrocytes. One of these was serotyped as O4:K-:H8, and a rabbit O antiserum raised against this strain allowed us to establish that 23 strains had the same O antigen. The 23 O4 strains were hemolytic and were not enterotoxic for rabbit ileal loops, and intact bacteria were able to destroy tissue culture cell monolayers very rapidly. The uniformity of the antibiotic resistance pattern and of the plasmid DNA content, together with the fact that they were isolated in different years and in different children, suggests that the O4 strains must be epidemiologically relevant in Somalia. A possible diarrheagenic role for the adherent-hemolytic E. coli strains is also discussed.

Adolescent↗
PubMed1993

Profile of Escherichia coli O157:H7 pathogen responsible for hamburger-borne outbreak of hemorrhagic colitis and hemolytic uremic syndrome in Washington.

We analyzed Escherichia coli O157:H7 isolates from stool samples of five patients who had bloody diarrhea and were infected during a large food-borne outbreak of hemorrhagic colitis in Washington state. The isolates were assessed for Shiga-like toxin profile, adherence and plasmid traits, mouse virulence, capsule, and enterohemolysin production. The profiles of the five isolates were indistinguishable from each other and similar to that of E. coli O157:H7 strain EDL933, an organism responsible for a similar hamburger-associated food poisoning episode in 1982.

Adolescent↗
PubMed2005

Virulence genotype and phylogenetic origin in relation to antibiotic resistance profile among Escherichia coli urine sample isolates from Israeli women with acute uncomplicated cystitis.

To clarify the virulence and phylogenetic implications of antimicrobial agent resistance in Escherichia coli, 100 E. coli isolates from urine samples of Israeli women with acute uncomplicated cystitis were analyzed by molecular phylotyping and virulence genotyping for comparison with resistance phenotypes. The differences between the isolates that were resistant and susceptible to trimethoprim-sulfamethoxazole and ampicillin were minimal. In contrast, ciprofloxacin resistance was associated with greatly reduced inferred virulence and categorical shifts away from the highly virulent phylogenetic group B2, which explained much of the virulence effect. The results of amplification fingerprinting suggested that most ciprofloxacin-resistant isolates represented unique clonal groups and were not derived from clonal groups with more highly virulent susceptible isolates. These findings suggest that virulence and antimicrobial resistance are not mutually exclusive in E. coli clinical isolates. Instead, the relationship between virulence and antimicrobial resistance varies according to the particular resistance phenotype; for ciprofloxacin resistance, the relationship is strongly influenced by phylogenetic background. The basis for the concentration of ciprofloxacin resistance in non-B2 phylogenetic groups remains unknown.

Acute Disease↗
PubMed2003

Intra-hospital dissemination of quinupristin/dalfopristin- and vancomycin-resistant Enterococcus faecium in a paediatric ward of a German hospital.

OBJECTIVES: To demonstrate nosocomial transmission of Enterococcus faecium resistant to quinupristin/dalfopristin and vancomycin/teicoplanin among paediatric patients in a German hospital ward. MATERIALS AND METHODS: Multiply-resistant E. faecium were isolated from three female patients aged 9 months, 2 and 15 years during a 10 day time span. Antibiotic susceptibilities were determined by microbroth dilution. Clonal relatedness among the isolates was investigated via SmaI-macrorestriction analysis by PFGE, multilocus sequence typing (MLST), and plasmid profiling. Presence of virulence and resistance determinants was tested by polymerase chain reaction (PCR). Selected resistance genes were localized by Southern hybridizations. RESULTS: A single E. faecium isolate per patient was investigated. All exhibited resistances to quinupristin/dalfopristin, vancomycin/teicoplanin, streptomycin (high-level), penicillin/ampicillin, erythromycin, oxytetracycline, chloramphenicol, rifampicin and fusidic acid. The isolates were susceptible to linezolid only and intermediately resistant to fluoroquinolones including moxifloxacin. PFGE revealed identical patterns for all three isolates. PCRs for virulence determinants hyaluronidase and enterococcal surface protein, esp, were negative, whereas PCR for the enterocin A gene was positive. MLST identified clonal type [8-5-1-1-1-1-1] belonging to a clonal subgroup C1 of hospital- and outbreak-related E. faecium. Southern hybridizations located several resistance genes (erm(B), vat(D), vanA) on a large plasmid, which was transferable in mating experiments with an E. faecium recipient. CONCLUSIONS: These data show routes of dissemination of resistance to multiple antibiotics including streptogramins and glycopeptides in E. faecium via vertical and/or horizontal gene transfer. The isolates spread in the absence of a direct selective pressure, as none of the patients had received earlier streptogramin or glycopeptide therapy.

Anti-Bacterial Agents↗
PubMed2005

Complete comparative genomic analysis of two field isolates of Mamestra configurata nucleopolyhedrovirus-A.

A second genotype of Mamestra configurata nucleopolyhedrovirus-A (MacoNPV-A), variant 90/4 (v90/4), was identified due to its altered restriction endonuclease profile and reduced virulence for the host insect, M. configurata, relative to the archetypal genotype, MacoNPV-A variant 90/2 (v90/2). To investigate the genetic differences between these two variants, the genome of v90/4 was sequenced completely. The MacoNPV-A v90/4 genome is 153 656 bp in size, 1404 bp smaller than the v90/2 genome. Sequence alignment showed that there was 99.5 % nucleotide sequence identity between the genomes of v90/4 and v90/2. However, the v90/4 genome has 521 point mutations and numerous deletions and insertions when compared to the genome of v90/2. Gene content and organization in the genome of v90/4 is identical to that in v90/2, except for an additional bro gene that is found in the v90/2 genome. The region between hr1 and orf31 shows the greatest divergence between the two genomes. This region contains three bro genes, which are among the most variable baculovirus genes. These results, together with other published data, suggest that bro genes may influence baculovirus genome diversity and may be involved in recombination between baculovirus genomes. Many ambiguous residues found in the v90/4 sequence also reveal the presence of 214 sequence polymorphisms. Sequence analysis of cloned HindIII fragments of the original MacoNPV field isolate that the 90/4 variant was derived from indicates that v90/4 is an authentic variant and may represent approximately 25 % of the genotypes in the field isolate. These results provide evidence of extensive sequence variation among the individual genomes comprising a natural baculovirus outbreak in a continuous host population.

Animals↗
PubMed2002

Clostridium septicum alpha-toxin is active against the parasitic protozoan Toxoplasma gondii and targets members of the SAG family of glycosylphosphatidylinositol-anchored surface proteins.

As is the case with many other protozoan parasites, glycosylphosphatidylinositol (GPI)-anchored proteins dominate the surface of Toxoplasma gondii tachyzoites. The mechanisms by which T. gondii GPI-anchored proteins are synthesized and transported through the unusual triple-membrane structure of the parasite pellicle to the plasma membrane remain largely unknown. As a first step in developing tools to study these processes, we show here that Clostridium septicum alpha-toxin, a pore-forming toxin that targets GPI-anchored protein receptors on the surface of mammalian cells, is active against T. gondii tachyzoites (50% effective concentration, 0.2 nM). Ultrastructural studies reveal that a tight physical connection between the plasma membrane and the underlying membranes of the inner membrane complex is locally disrupted by toxin treatment, resulting in a massive outward extension of the plasma membrane and ultimately lysis of the parasite. Toxin treatment also causes swelling of the parasite endoplasmic reticulum, providing the first direct evidence that alpha-toxin is a vacuolating toxin. Alpha-toxin binds to several parasite GPI-anchored proteins, including surface antigen 3 (SAG3) and SAG1. Interestingly, differences in the toxin-binding profiles between the virulent RH and avirulent P strain were observed. Alpha-toxin may prove to be a powerful experimental tool for molecular genetic analysis of GPI anchor biosynthesis and GPI-anchored protein trafficking in T. gondii and other susceptible protozoa.

Animals↗
PubMed2006

Genomic comparison of Escherichia coli K1 strains isolated from the cerebrospinal fluid of patients with meningitis.

Escherichia coli is a major cause of enteric/diarrheal diseases, urinary tract infections, and sepsis. E. coli K1 is the leading gram-negative organism causing neonatal meningitis, but the microbial basis of E. coli K1 meningitis is incompletely understood. Here we employed comparative genomic hybridization to investigate 11 strains of E. coli K1 isolated from the cerebrospinal fluid (CSF) of patients with meningitis. These 11 strains cover the majority of common O serotypes in E. coli K1 isolates from CSF. Our data demonstrated that these 11 strains of E. coli K1 can be categorized into two groups based on their profile for putative virulence factors, lipoproteins, proteases, and outer membrane proteins. Of interest, we showed that some open reading frames (ORFs) encoding the type III secretion system apparatus were found in group 2 strains but not in group 1 strains, while ORFs encoding the general secretory pathway are predominant in group 1 strains. These findings suggest that E. coli K1 strains isolated from CSF can be divided into two groups and these two groups of E. coli K1 may utilize different mechanisms to induce meningitis.

Bacterial Outer Membrane Proteins↗
PubMed2006

Molecular epidemiologic identification of Escherichia coli genes that are potentially involved in movement of the organism from the intestinal tract to the vagina and bladder.

A first step in urinary tract infection (UTI) pathogenesis in the otherwise healthy host is the movement of uropathogenic Escherichia coli from the intestinal tract to the urinary tract. We conducted a genomic subtraction to isolate genetic regions associated with this movement. A representative UTI isolate present in the rectum, vagina, and bladder of a woman with UTI was chosen as the tester; the driver was a phylogenetically distant rectal isolate (based on pulsed-field gel electrophoresis analysis) with a profile of uropathogenic virulence genes similar to that of the tester. Tester-specific regions identified by the subtraction were screened, using DNA dot blot hybridization, against a collection of 88 uropathogens isolated from the rectum, urine, and/or vagina of women with UTIs and 54 E. coli isolates from the same women that were found only in the rectum. Twelve genetic regions occurred more often in multisite isolates than in rectal site-only isolates. Eleven of these 12 genetic regions are homologous to regions in the sequenced uropathogenic E. coli CFT073 strain.

Cluster Analysis↗
PubMed1997

Lancefield grouping and smell of caramel for presumptive identification and assessment of pathogenicity in the Streptococcus milleri group.

AIM: To evaluate Lancefield grouping and caramel smell for presumptive identification of the Streptococcus milleri group, and to find whether Lancefield group, species, or protein profile correlated with virulence or infection site. METHODS: Prospective studies were made of 100 consecutive streptococcal isolates in blood cultures or pus from 100 patients in whom the severity of infection was categorised as serious, moderate, or not significant. The usefulness of Lancefield group and the caramel smell for presumptive identification was examined, and the relation of the S milleri species, Lancefield group, and SDS-PAGE protein analysis to severity of infection and infection site was investigated. Lower respiratory tract and genital tract specimens, strict anaerobes, group D streptococci, and strains identified as Streptococcus pneumoniae, Streptococcus pyogenes, or Streptococcus agalactiae were excluded. RESULTS: Most streptococci occurring in pure or significant growth density were S milleri group (87/100; 87%, 95% confidence interval 0.81-0.93). Of these, 89.7% (78/87; 0.84-0.96) were associated with infection. Lancefield group F antigen predominated (41/87; 47.1%, 0.38-0.56). Lancefield group F alone or accompanied by the caramel smell had a specificity of 100%, but a sensitivity of only 47.3% for group F alone, and 19.5% for group F accompanied by the caramel smell. There was no significant association between species, Lancefield group, and severity of infection, site of infection, or pathogenicity. SDS-PAGE analysis failed to discriminate between strains. CONCLUSIONS: Neither species nor Lancefield antigen was related to the site of infection. The presence of Lancefield group F antigen alone or accompanied by a caramel smell was a useful indicator for the S milleri group when present, but was too insensitive to use as a screening test. Most streptococci occurring in pure culture or in significant growth density were of clinical importance. Such organisms should be identified to species level to detect the S milleri group.

Bacterial Proteins↗
PubMedDate not supplied

[Helicobacter pylori. I. Morphology, biochemistry, antigenic profile and correlated diseases].

Infection by Helicobacter pylori (HP) occurs all over the world and is related to the socio-economic development of the subject's country of residence and age. Various strains of HP can be identified on the basis of the microbiological characteristics of the bacterium and, in particular, or its antigenic profile, while the virulence factors are responsible for the damage that HP can cause. The virulence factors include components (flagellum and adhesin) and substances produced by bacterium (enzymes and cytotoxins), the most important among which are urease and the cytotoxins, CagA and VacA. It is the association of these virulence factors that is responsible for the different pathologies to which HP-positive subjects are prone. The link between HP and gastritis, peptic ulcer and gastric cancers (adenocarcinoma and lymphoma) is now proven. Whether there is a link between HP and RAP in young children is still a matter for debate; some Authors claim that there is, while others refute it.

Adult↗
PubMed1984

Difference in the extracellular products of two strains of Aeromonas hydrophila virulent and weakly virulent for fish.

In this study we first compared the toxigenic profile of Aeromonas hydrophila strains virulent and weakly virulent for rainbow trout. The separation of the toxic factor for fish is also described. Both strains produced hemolytic, enterotoxic, and dermonecrotic activities; the weakly virulent strain produced 20 times more hemolysin. Only the cell-free supernatant of the virulent strain produced a toxic factor for fish. After passage on Sephacryl S-200, the toxic factor for fish was separated from the hemolysin. This toxic factor is heat labile.

Aeromonas↗
PubMed2002

Molecular characterisation of the dominant UK methicillin-resistant Staphylococcus aureus strains, EMRSA-15 and EMRSA-16.

Epidemic methicillin-resistant Staphylococcus aureus types 15 and 16 (EMRSA-15 and EMRSA-16) are the dominant types of MRSA found in UK hospitals, but accurate designation of strains has been difficult. Restriction fragment length polymorphism (RFLP) profiles of seven core virulence genes were used to classify unambiguously isolates of MRSA from St George's Hospital into two groups corresponding to EMRSA-15 and EMRSA-16. Variants of both EMRSA-15 and EMRSA-16 isolates occurred that had lost virulence genes encoded on mobile genetic elements. EMRSA-16 isolates had core gene profiles identical to a cluster of previously characterised MSSA (methicillin-sensitive S. aureus) isolates from St George's Hospital, suggesting that they have arisen from this source, or that loss of the accessory genetic element encoding methicillin resistance is frequent. EMRSA-15 and EMRSA-16 strains were distinct from other MRSA strains previously identified in UK hospitals, and always carried a mobile genetic element encoding multiple superantigens. These results contribute to the understanding of the types of MRSA found in UK hospitals, how they vary and how they arose.

Blotting, Southern↗