Abstract:
:Most Shiga toxin-producing Escherichia coli (STEC) strains associated with severe disease, such as hemolytic-uremic syndrome (HUS), carry large enterohemolysin-encoding (ehxA) plasmids, e.g., pO157 and pO103, that contribute to STEC clinical manifestations. Six ehxA subtypes (A through F) exist that phylogenetically cluster into eae-positive (B, C, F), a mix of eae-positive (E) and eae-negative (A), and a third, more distantly related, cluster of eae-negative (D) STEC strains. While subtype B, C, and F plasmids share a number of virulence traits that are distinct from those of subtype A, sequence data have not been available for subtype D and E plasmids. Here, we determined and compared the genetic composition of four subtype D and two subtype E plasmids to establish their evolutionary relatedness among ehxA subtypes and define their potential role in pathogenicity. We found that subtype D strains carry one exceptionally large plasmid (>200 kbp) that carries a variety of virulence genes that are associated with enterotoxigenic and enterohemorrhagic E. coli, which, quite possibly, enables these strains to cause disease despite being food isolates. Our data offer further support for the hypothesis that this subtype D plasmid represents a novel virulence plasmid, sharing very few genetic features with other plasmids; we conclude that these plasmids have evolved from a different evolutionary lineage than the plasmids carrying the other ehxA subtypes. In contrast, the 50-kbp plasmids of subtype E (pO145), although isolated from HUS outbreak strains, carried only few virulence-associated determinants, suggesting that the clinical presentation of subtype E strains is largely a result of chromosomally encoded virulence factors. IMPORTANCE:Bacterial plasmids are known to be key agents of change in microbial populations, promoting the dissemination of various traits, such as drug resistance and virulence. This study determined the genetic makeup of virulence plasmids from rare enterohemolysin subtype D and E Shiga toxin-producing E. coli strains. We demonstrated that ehxA subtype D plasmids represent a novel E. coli virulence plasmid, and although subtype D plasmids were derived from nonclinical isolates, they encoded a variety of virulence determinants that are associated with pathogenic E. coli In contrast, subtype E plasmids, isolated from strains recovered from severely ill patients, carry only a few virulence determinants. The results of this study reemphasize the plasticity and vast diversity among E. coli plasmids. This work demonstrates that, although E. coli strains of certain serogroups may not be frequently associated with disease, they should not be underestimated in protecting human health and food safety.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Lorenz SC,Monday SR,Hoffmann M,Fischer M,Kase JAdoi
10.1128/AEM.01839-16subject
Has Abstractpub_date
2016-10-14 00:00:00pages
6367-6377issue
21eissn
0099-2240issn
1098-5336pii
AEM.01839-16journal_volume
82pub_type
杂志文章abstract::Botulinum neurotoxin (BoNT), produced by neurotoxigenic clostridia, is the most potent biological toxin known and the causative agent of the paralytic disease botulism. The nutritional, environmental, and genetic regulation of BoNT synthesis, activation, stability, and toxin complex (TC) formation is not well studied....
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00642-17
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.57.7.1905-1913.1991
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abstract::A new design, flat-bottom combination pH electrode was evaluated for utility in determining the pH of prepared agar media by surface contact of the electrode with the agar media. ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.34.2.242-243.1977
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.11.3939-3947.1996
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.42.3.544-545.1981
更新日期:1981-09-01 00:00:00
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journal_title:Applied and environmental microbiology
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journal_title:Applied and environmental microbiology
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abstract::Antibody against nivalenol tetraacetate (tetra-Ac-NIV) was prepared by immunization of rabbits with triacetyl-15-pimelate-NIV conjugated to bovine serum albumin. By using tritiated tetra-Ac-NIV as the test ligand, antibody titers were demonstrated as early as 4 weeks after immunization. Useful antibody for radioimmuno...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.57.4.1026-1030.1991
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02303-19
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.67.7.3264-3268.2001
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.65.11.4967-4972.1999
更新日期:1999-11-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.43.3.643-647.1982
更新日期:1982-03-01 00:00:00
abstract::The intraspecific genomic relatedness of 80 Vibrio vulnificus isolates, 44 of biotype 1 and 36 of biotype 2, from different geographic origins and sources was evaluated by ribotyping and AFLP (amplified fragment length polymorphism) fingerprinting. Ribopatterns of DNAs digested with KpnI and hybridized with an oligonu...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.63.7.2600-2606.1997
更新日期:1997-07-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.57.3.642-644.1991
更新日期:1991-03-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00671-19
更新日期:2019-06-17 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.68.9.4613-4622.2002
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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更新日期:1997-02-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.67.8.3702-3706.2001
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journal_title:Applied and environmental microbiology
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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journal_title:Applied and environmental microbiology
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doi:10.1128/AEM.44.3.737-743.1982
更新日期:1982-09-01 00:00:00
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journal_title:Applied and environmental microbiology
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abstract::A 1.5-kb region immediately downstream of the styABCD operon involved in styrene degradation in Pseudomonas putida CA-3 has been cloned. Sequence analysis revealed a 1,296-bp open reading frame, designated styE, and BLAST P database comparisons of the deduced StyE amino acid sequence revealed 33 to 98% identity with s...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.72.2.1302-1309.2006
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abstract::Significant amounts of ethylene were produced by Pseudomonas syringae pv. glycinea, pv. phaseolicola (which had been isolated from viny weed Pueraria lobata [Willd.] Ohwi [common name, kudzu]), and pv. pisi in synthetic medium. On the other hand, the bean strains of P. syringae pv. phaseolicola and strains of 17 other...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.63.1.156-161.1997
更新日期:1997-01-01 00:00:00
abstract::Dental caries is one of the most common diseases worldwide. Bacteria and fungi are both commensals in the oral cavity; however, most research regarding caries has focused on bacterial impacts. The oral fungal mycobiome associated with caries is not well characterized, and its role in disease is unclear. ITS1 amplicon ...
journal_title:Applied and environmental microbiology
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更新日期:2020-03-18 00:00:00
abstract::Nested PCR with three highly degenerate primers was used for amplification and identification of DNA polymerase (pol) genes from viruses which infect three genera of microalgae. Group-specific primers (AVS1 and AVS2) were designed on the basis of inferred amino acid sequences unique to the DNA pol genes of viruses (PB...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.61.4.1274-1278.1995
更新日期:1995-04-01 00:00:00
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journal_title:Applied and environmental microbiology
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doi:10.1128/AEM.37.1.85-90.1979
更新日期:1979-01-01 00:00:00
abstract::Under anoxic conditions, most methoxylated mononuclear aromatic compounds are degraded by bacteria, with catechol being formed as an important intermediate. On the basis of our experiments with the sulfate-reducing bacterium Desulfobacterium sp. strain Cat2, we describe for the first time the enzymatic activities invo...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.60.9.3396-3400.1994
更新日期:1994-09-01 00:00:00
abstract::Accurate enumeration of viruses within environmental samples is critical for investigations of the ecological role of viruses and viral infection within microbial communities. This report evaluates differences in viral and bacterial direct counts between estuarine sediment samples which were either immediately process...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00297-06
更新日期:2006-07-01 00:00:00