| 1. |
- Johanson, I M, et al.
(författare)
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Pap, papG and prsG DNA sequences in Escherichia coli from the fecal flora and the urinary tract.
- 1993
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Ingår i: Microbial pathogenesis. - : Elsevier BV. - 0882-4010. ; 15:2, s. 121-9
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Tidskriftsartikel (refereegranskat)abstract
- The pap gene clusters encode P fimbriae and fimbriae-associated G adhesins. DNA sequence analysis has resolved three G adhesin variants (papGJ96, papGIA2 and prsGJ96) that differ in receptor specificity and therefore in binding to epithelial cells. In this study, DNA probes specific for the pap gene cluster or the papGJ96, papGIA2 and prsGJ96 adhesin sequences were used to examine 74 fecal and 204 urinary Escherichia coli isolates (67 from acute pyelonephritis, 71 from acute cystitis and 66 from asymptomatic bacteriuria). In accordance with previous studies, a higher frequency of pap+ strains was found in the urinary strains (71%) than in the fecal (20%) E. coli isolates. The papGIA2, and prsGJ96 sequences were more frequent among urinary (42% papG+IA2, 23% prsG+J96) than among fecal (18% papG+IA2, 5% prsG+J96) isolates. None of the isolates hybridized with the papGJ96 probe. Pap+ strains accounted for 82% of the pyelonephritis, 69% of the cystitis and 61% of the asymptomatic bacteriuria strains. The papGIA2 genotype dominated in acute pyelonephritis strains (72% papG+IA2, 16% prsG+J96). The prsGJ96 genotype was most frequent in cystitis strains (25% papG+IA2, 37% prsG+J96). The asymptomatic bacteriuria strains formed an intermediate group (30% papG+IA2, 14% prsG+J96). Most of the papG+IA2 strains expressed P fimbriae which agglutinated human erythrocytes, sheep erythrocytes and Gal alpha 1-4Gal beta latex beads. The prsG+J96 strains varied in agglutination of human and sheep erythrocytes and Gal alpha 1-4Gal beta-latex beads. The results demonstrated that the papGIA2 and prsGJ96 adhesin DNA sequences differ in disease association.
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| 2. |
- Plos, Kaety, 1944, et al.
(författare)
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Escherichia coli in patients with renal scarring: genotype and phenotype of Gal alpha 1-4Gal beta-, Forssman- and mannose-specific adhesins.
- 1991
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Ingår i: The Pediatric infectious disease journal. - 0891-3668. ; 10:1, s. 15-9
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Tidskriftsartikel (refereegranskat)abstract
- The frequency of Escherichia coli with Gal alpha 1-4Gal beta-specific adhesins is reduced among children who develop renal scars. The adhesion-negative phenotype may be due to the absence of the pap DNA sequences which encode these adhesins or to a phase variation event induced by in vitro culture. In the present study the frequency of pap and pil homologous DNA was determined by dot blot analysis with probes specific for the respective sequence using E. coli strains from children with recurrent pyelonephritis with and without renal scarring. The frequency of pap was 79% in the strains isolated from the nonscarring group compared with 39% in the strains from the scarring group (P less than 0.001). The Gal alpha 1-4Gal beta phenotype was expressed by 89% of the pap-positive strains from the nonscarring group compared with 71% in the scarring group (P less than 0.05). In addition 13 of 77 of the pap-positive E. coli strains agglutinated sheep erythrocytes but not the Gal alpha 1-4Gal beta latex beads; a reaction attributed to reactivity with the Forssman glycolipid. DNA sequences homologous with pil were found in 95% of all strains and there was no significant difference between the nonscarring and the scarring groups. The low frequency of Gal alpha 1-4Gal beta specific strains in the scarring group was therefore due to the absence of pap-homologous DNA sequences and to a reduced rate of phenotypic expression among pap-positive scarring strains. There was no support for a relationship between type 1 fimbriae and renal scarring.
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| 3. |
- Plos, Kaety, 1944, et al.
(författare)
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Frequency and organization of pap homologous DNA in relation to clinical origin of uropathogenic Escherichia coli.
- 1990
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Ingår i: The Journal of infectious diseases. - 0022-1899. ; 161:3, s. 518-24
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Tidskriftsartikel (refereegranskat)abstract
- The pap operon encodes the gal alpha 1-4gal beta specific adhesins of Escherichia coli. The presence and organization of pap homologous DNA was determined using two probes specific for pap in 217 uropathogenic E. coli samples by dot blot and Southern blot analysis. The frequency of pap homologous DNA was 76% in pyelonephritis, 69% in cystitis, and 52% in an asymptomatic bacteriuria group. Further, the gal alpha 1-4gal beta binding phenotype among the pap-positive strains was expressed more often in acute pyelonephritis (91%) than the cystitis (60%) or asymptomatic bacteriuria (52%) strains. This was explained in part by difference in organization of pap homologous DNA between the genotypically positive pyelonephritis and asymptomatic bacteriuria strains. The pyelonephritis isolates contained three copies of pap significantly more often than the asymptomatic bacteriuria strains, and the pyelonephritogenic O-antigen types had a general increase in pap copy number. The difference in expression of gal alpha 1-4gal beta adhesins between pyelonephritis and asymptomatic bacteriuria isolates was thus not only a function of the frequency of pap homologous DNA but also of phenotypic expression among genotypically pap-positive strains.
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