Coli surface antigens 1 and 3 of colonization factor antigen II-positive enterotoxigenic Escherichia coli: morphology, purification, and immune responses in humans

Abstract

Enterotoxigenic Escherichia coli (ETEC) of serotype 06:H16, biotype A, bearing colonization factor antigen II (CFA/II) possesses two distinct coli surface antigens, CS1 and CS3, whereas CFA/II-positive ETEC of serotype 08:H9 manifests only CS3. CS1 has been shown to be fimbrial in nature, but heretofore the morphology of CS3 has not been described. Accordingly, by immune electron microscopy we investigated the morphological characteristics of CS3 on bacterial cells and after purification. CS3 was found to consist of thin (2-nm), flexible, wiry, "fibrillar" fimbriae, visible both on bacteria (06:H16, biotype A, and 08:H9 strains) and in the pure state. In contrast, CS1 exists as wider (6-nm), rigid fimbriae on the surface of 06:H16, biotype A, strains. By the use of antisera to CS1 and CS3 in immune electron microscopy, immunodiffusion in gel, and immunoblotting techniques, CS1 and CS3 were found to be immunologically as well as morphologically distinct. Six of nine volunteers who developed diarrhea after challenge with an 0139:H28 ETEC strain bearing CS1 and CS3 had significant serological rises to purified CS1 and CS3 antigens, suggesting that both antigens are elaborated in vivo, play a role in pathogenesis, and stimulate an immune response.

Adhesive organelles of Gram-negative pathogens assembled with the classical chaperone/usher machinery: structure and function from a clinical standpoint

“…This denser capsular material, likely composed of aggregates of the thin fibrils, sometimes extended out from the bacterial surface in long strands. The thin, fibrillar appearance of the F1 capsule resembles structures previously reported for other members of the FGL family of chaperone/ usher pathways, including the pH6 antigen of Yersinia (Iriarte et al, 1993;Lindler & Tall, 1993) and the CS3 and CS6 pili of ETEC (Levine et al, 1984;Knutton et al, 1989). This supports a common structure and assembly mechanism for members of the FGL family.…”

Characterization of blue light irradiation effects on pathogenic and nonpathogenic Escherichia coli

“…The studies described in this work demonstrate that BLI treatment does not significantly impair E. coli viability and suggest that the use of BLI as an antimicrobial strategy may retard the growth of some strains, possibly including commensals, while conferring an advantage to pathogenic/opportunistic bacteria or bacteria found at a different phase of growth. For example, our findings demonstrated that UPEC strain EC958, a multi-drug ST131 lineage E. coli (Totsika et al, 2011) and ETEC strain E9034A (Levine et al, 1984) were the least susceptible to the effects of BLI 455 ; however, nonpathogenic E343 (Rúgeles et al, 2010) was also significantly resistant to the effects of BLI 455 . These findings have wide-ranging ramifications in the way phototherapy may be used to treat or prevent infections.…”

“…The following E. coli strains were used: phylogenetic group A strains DH5α [laboratory-adapted (Laboratories, 1986)] and MG1655 [K-12 (Bachmann, 1996)]; group B1 strains E343 and E402 [nonpathogenic isolates (Rúgeles, Bai, Martínez, Vanegas, & Gómez-Duarte, 2010)]; group B2 UPEC strains UTI89 (Mulvey et al, 1998) and EC958 (Totsika et al, 2011); group D enterotoxigenic (ETEC) strain E9034A (Levine et al, 1984); and group E enterohemorrhagic (EHEC) O157:H7 strain Sakai (Hayashi et al, 2001).…”

Weapons of mass destruction: virulence factors of the global killer EnterotoxigenicEscherichia coli

“…These DNA fragments have a lower GC content and codon usage than normally associated with E. coli and are generally flanked by insertion sequences and transposons (Gaastra & Svennerholm, 1996;. While some strains possess multiple CFs, most ETEC strains have no known CF, either because it is novel and as yet unidentified or has been lost in laboratory subculture (Levine et al, 1984;Valvatne et al, 2002). More than 20 CFs with distinct molecular weight subunits have been identified and characterized ( Table 1).…”