Clonal analysis of Escherichia coli serotype O6 strains from urinary tract infections

Zingler, Gerhard; Ott, Manfred; Blum, Gabriele; Falkenhagen, U; G, Naumann; Sokolowska-Köhler, W; Hacker, Jörg

doi:10.1016/0882-4010(92)90048-s

Cited by 24 publications

(12 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sixteen strains were isolated from humans with septicemia: eight from the blood of newborns without meningitis (61), seven from adults with septicemia in France (this study), and one from a septicemic patient in Hungary (10). Fifteen strains were from urinary tract infections, including one strain from Hungary (10), five from Germany (68,69), six from the ECOR collection (44) (http://foodsafe.msu.edu/whittam/ecor), and the UPEC type strains CFT073, 536, and J96 (22,43,62). Four animal ExPEC strains were isolated from cases of septicemia in a sheep (S5), a pig (P72), and calves (BM2-1 and Orne6) (9,13,45,56).…”

Section: Methodsmentioning

confidence: 99%

Extraintestinal Pathogenic Escherichia coli Strains of Avian and Human Origin: Link between Phylogenetic Relationships and Common Virulence Patterns

et al. 2007

View full text Add to dashboard Cite

Extraintestinal pathogenic Escherichia coli (ExPEC) strains of human and avian origin show similarities that suggest that the avian strains potentially have zoonotic properties. However, the phylogenetic relationships between avian and human ExPEC strains are poorly documented, so this possibility is difficult to assess. We used PCR-based phylotyping and multilocus sequence typing (MLST) to determine the phylogenetic relationships between 39 avian pathogenic E. coli (APEC) strains of serogroups O1, O2, O18, and O78 and 51 human ExPEC strains. We also compared the virulence genotype and pathogenicity for chickens of APEC strains and human ExPEC strains. Twenty-eight of the 30 APEC strains of serogroups O1, O2, and O18 were classified by MLST into the same subcluster (B2-1) of phylogenetic group B2, whereas the 9 APEC strains of serogroup O78 were in phylogenetic groups D (3 strains) and B1 (6 strains). Human ExPEC strains were closely related to APEC strains in each of these three subclusters. The 28 avian and 25 human strains belonging to phylogenetic subcluster B2-1 all expressed the K1 antigen and presented no significant differences concerning the presence of other virulence factors. Moreover, human strains of this phylogenetic subcluster were highly virulent for chicks, so no host specificity was identified. Thus, APEC strains of serotypes O1:K1, O2:K1, and O18:K1 belong to the same highly pathogenic clonal group as human E. coli strains of the same serotypes isolated from cases of neonatal meningitis, urinary tract infections, and septicemia. These APEC strains constitute a potential zoonotic risk.

show abstract

Section: Methodsmentioning

confidence: 99%

Extraintestinal Pathogenic Escherichia coli Strains of Avian and Human Origin: Link between Phylogenetic Relationships and Common Virulence Patterns

et al. 2007

View full text Add to dashboard Cite

show abstract

“…As UPEC clinical strains, we used E. coli J96 (17) and an isolate (RZ422) from the collection of the "Institut für Molekulare Infektionsbiologie der Universität Würzburg" obtained from patients suffering from either cystitis or pyelonephritis (39). E. coli LE392 was transformed using either a pISS391 cosmid or empty vector pHC79 (20), resulting in the K12/cnf1 ϩ strain and LE392/pHC79, respectively.…”

Section: Methodsmentioning

confidence: 99%

Active Cytotoxic Necrotizing Factor 1 Associated with Outer Membrane Vesicles from Uropathogenic Escherichia coli

et al. 2006

View full text Add to dashboard Cite

Cytotoxic necrotizing factor type 1 (CNF1) is one of the virulence factors produced by uropathogenic Escherichia coli (UPEC). How this toxin is translocated from the bacterial cytoplasm to the surrounding environment is not well understood. Our data suggest that CNF1 may be regarded as a secreted protein, since it could be detected in culture supernatants. Furthermore, we found that CNF1 was tightly associated to outer membrane vesicles, suggesting that such vesicles play a role in the secretion of this protein. Interestingly, vesicle samples containing CNF1 could exert the effects known for this protein on HeLa cell cultures, showing that CNF1 is transported by vesicles in its active form. Taken together, our results strongly suggest that outer membrane vesicles could be a means for the bacteria to deliver CNF1 to the environment and to the infected tissue. In addition, our results indicate that the histone-like nucleoid structuring protein H-NS has a role in the downregulation of CNF1 production and that it affects the outer membrane vesicle release in UPEC strain J96.Uropathogenic Escherichia coli (UPEC) strains are responsible for at least 80% of human urinary tract infections (UTIs), which include urethritis, cystitis, and pyelonephritis (21). UTI is among the most common bacterial infections in humans and has been shown to be an independent risk factor for both bladder cancer and renal cell carcinoma (30). To achieve pathogenicity, the UPEC strains produce many virulence factors such as adhesins (P and type 1 pili), hemolysin, aerobactin siderophore system, a capsule, and cytotoxic necrotizing factor type 1 (CNF1). CNF1 belongs to a group of bacterial necrotic substances which include the dermonecrotic toxin of Bordetella spp. (14), the virulence plasmid-encoded CNF2 of E. coli (14,29), and the recently described CNFy from Yersinia pseudotuberculosis (24). Unlike CNFy, whose mechanism of action is specific to RhoA (13), CNF1 affects three proteins of the Rho family of the small GTPases: RhoA, Rac1, and Cdc42. CNF1 deamidates Gln63 of RhoA (or the corresponding Gln61 of Rac1 and Cdc42), leading to the loss of both intrinsic and GAP-stimulated GTPase activities but without affecting the GTP-binding activity (14). This modification renders these GTPases constitutively active, which commonly results in formation of cellular actin stress fibers, filopodia and lamellipodia, with an overall effect of blocking the cytokinesis, leading to giant multinucleated cells (7,23,25). CNF1 is a 115-kDa A-B toxin, in which a catalytic A domain is located in the C-terminal region of about 300 amino acids and where the cell binding B-domain is in the N-terminal region (amino acids 53 to 190) (6,22). No typical signal peptide is found in the CNF1 sequence, and the secretion pathway of this toxin remains unclear. In this work we show that CNF1 is secreted and that it is associated with membrane vesicles. Furthermore, we present evidence that CNF1 is down regulated by H-NS (histone-like nucleoid structuring protein). MATERIALS AN...

show abstract

“…The sheA gene was deleted in the 14 uropathogenic E. coli (UPEC) strains examined by Ludwig et al in a recent study (16). Their 14 UPEC strains, including the well-known hlyA ϩ J96 and 536 strains, were assayed for the presence of an hlyA fragment by Southern blot hybridization, but it was identified in only 10 of the 14 strains (28,29). In our study, we found that 47.1% of the 486 UPEC strains contained the sheA gene ( Table 3).…”

mentioning

confidence: 99%

Occurrence of hlyA and sheA Genes in Extraintestinal Escherichia coli Strains

Kerényi¹,

Allison

Bátai

et al. 2005

J Clin Microbiol

View full text Add to dashboard Cite

The association of a hemolytic phenotype with the carriage of the ␣-hemolysin gene (hlyA) and/or the silent hemolysin gene (sheA or clyA) among 540 extraintestinal clinical isolates of Escherichia coli and 110 fecal isolates from healthy individuals was investigated. Though HlyA is an important virulence factor in extraintestinal E. coli infection, the role of SheA is not completely clarified. Two hemolytic sheA ؉ E. coli strains that lacked hlyA and possessed no other hemolysin genes were identified. No hlyA ؉ sheA ؉ strains were identified, suggesting that there is possible incompatibility between hlyA and sheA in the chromosome of E. coli.

show abstract

Clonal analysis of Escherichia coli serotype O6 strains from urinary tract infections

Cited by 24 publications

References 53 publications

Extraintestinal Pathogenic Escherichia coli Strains of Avian and Human Origin: Link between Phylogenetic Relationships and Common Virulence Patterns

Extraintestinal Pathogenic Escherichia coli Strains of Avian and Human Origin: Link between Phylogenetic Relationships and Common Virulence Patterns

Active Cytotoxic Necrotizing Factor 1 Associated with Outer Membrane Vesicles from Uropathogenic Escherichia coli

Occurrence of hlyA and sheA Genes in Extraintestinal Escherichia coli Strains

Contact Info

Product

Resources

About