Volume 2, Number 4—October 1996
Synopsis
Molecular Mechanisms of Bacterial Virulence: Type III Secretion and Pathogenicity Islands
Table 2
Characteristics of several pathogenicity islands
| Organism | Name | Location | Borders | Stable ? | Foreign origin G+C: % island/ % chromosome | Functions | Size | Ref. |
|---|---|---|---|---|---|---|---|---|
| Uropathogenic E. coli 536 | Pathogenicity island I, Pai I | selCa, 82' | • 16 bp direct repeats, derived from selC • shared motif with Pai II repeats | no | direct repeats absent from normal fecal and laboratory strains of E. coli | -hemolysin I | 70 kb | 3, 82, 84 |
| Pai II | leuXa, 97' | • 18 bp direct repeats, derived from leuX • shared motif with Pai I repeats | no | direct repeats absent from normal fecal and laboratory strains of E. coli | -hemolysin II prf (fimbriae: adherence to host cells) transcriptional activators of chromosomal genes | 190 kb | 3,4, 67, 82, 84 | |
| Uropathogenic E. coli J96 | Pai I | near pheVa, 64' | absent from normal fecal and laboratory strains of E. coli | -hemolysin I pap (fimbriae: adherence to host cells) IS element sequences R plasmid sequences P4 phage sequences | >170 kb | 96 | ||
| Pai II | pheRa, 94' | 135 bp imperfect direct repeats | no | direct repeats absent from normal fecal and laboratory strains of E. coli | -hemolysin II prs (fimbriae: adherence to host cells) cytotoxic necrotizing factor type 1 IS element sequences P4 phage sequences OmpR homolog | 106 kb | 4, 96, 97 | |
| Entero-pathogenic E. coli (EPEC) | Locus of enterocyte effacement, LEE | selCa, 82' | no repeats or IS elements found | yesb | G+C: 39%/51% not present in closely related, non-AE-producing bacteria | mediates formation of AE lesions type III secretion system | 35 kb | 63, 83 |
| Salmonella typhimurium | Salmonella pathogenicity island 1, SPI 1 | between fhl and mutS, 63' | no repeats or IS elements found in S. typhimurium; IS3 on one border in certain Salmonella serotypes | yesb,c | G+C: 42%/52% absent from E. coli | invasion into cultured epithelial cells type III secretion system | 40 kb | 28, 68 |
| SPI 2 | between ydhE and pykF, 31' | yesb | G+C: 45%/52% absent from E. coli; conserved among Salmonella | type III secretion system | 40 kb | 43 | ||
| Salmonella induced filament gene A, sifA | potB/ potC | 14 bp direct repeats | yes | G+C: 41%/52% direct repeats absent in E. coli; conserved among Salmonella | required for formation of structures associated with Salmonella-associated vacuoles within epithelial cells | 1.6 kb | 69d | |
| Yersinia pestis | Ability to adsorb exogenous pigments, Pgm | phoE | 2.2 kb direct repeats (=IS100) | no | G+C: hemin storage region 47%/46-50%; yersiniabactin receptor/ iron-regulated protein region 56-60%/46-50% direct repeats | hemin and congo red binding pesticin sensitivity iron acquisition growth at 37 C in defined medium | 102 kb | 70, 71 |
| Helicobacter pylori | Cytotoxin-associated gene region, Cag | glr | • 31 bp direct repeats, derived from glutamate racemase gene • IS605 on one end | see text | G+C: 35%/38-45% IS elements not present in type II strains | induction of IL-8 secretion homologues to membrane-associated proteins: environmental sensors, translocases, permeases, pilus and flagella assembly proteins IS elements | 40 kb | e |
| Vibrio cholerae O139 | otnA otnB | rfb | flanked by two different IS elements | IS elements not present in Vibrio cholerae O1 El Tor | capsule and O antigen synthesis (by homology) | 35 kb | 93, 98 | |
| Listeria monocytogenes | between prs and ldh | No IS elements found | yesb | not present in several nonpathogenic species | escape from vacuole intra-/inter-cellular spread | 9.6 kb | 99 |
atRNA gene
bapparently
cunstable in certain serotypes
dadditional information received in personal communication with M. Stein
eCensini S, et al., 1996, submitted for publication
