Distribution of Core Oligosaccharide Types in Lipopolysaccharides from Escherichia coli
AUTOR(ES)
Amor, Karen
FONTE
American Society for Microbiology
RESUMO
In the lipopolysaccharides of Escherichia coli there are five distinct core oligosaccharide (core OS) structures, designated K-12 and R1 to R4. The objective of this work was to determine the prevalences of these core OS types within the species. Unique sequences in the waa (core OS biosynthesis) gene operon were used to develop a PCR-based system that facilitated unequivocal determination of the core OS types in isolates of E. coli. This system was applied to the 72 isolates in the E. coli ECOR collection, a compilation of isolates that is considered to be broadly representative of the genetic diversity of the species. Fifty (69.4%) of the ECOR isolates contained the R1 core OS, 8 (11.1%) were representatives of R2, 8 (11.1%) were R3, 2 (2.8%) were R4, and only 4 (5.6%) were K-12. R1 is the only core OS type found in all four major phylogenetic groups (A, B1, B2, and D) in the ECOR collection. Virulent extraintestinal pathogenic E. coli isolates tend to be closely related to group B2 and, to a lesser extent, group D isolates. All of the ECOR representatives from the B2 and D groups had the R1 core OS. In contrast, commensal E. coli isolates are more closely related to group A, which contains isolates representing each of the five core OS structures. R3 was the only core OS type found in 38 verotoxigenic E. coli (VTEC) isolates from humans and cattle belonging to the common enterohemorrhagic E. coli serogroups O157, O111, and O26. Although isolates from other VTEC serogroups showed more core OS diversity, the R3 type (83.1% of all VTEC isolates) was still predominant. When non-VTEC commensal isolates from cattle were analyzed, it was found that most possessed the R1 core OS type.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=97256Documentos Relacionados
- Mechanisms involved in protection provided by immunization against core lipopolysaccharides of Escherichia coli J5 from lethal Haemophilus pleuropneumoniae infections in swine.
- Characterization of lipopolysaccharides from Escherichia coli K-12 mutants.
- Distribution of R Plasmids Among the O-Antigen Types of Escherichia coli Isolated from Various Clinical Sources
- Crystallization of R-form lipopolysaccharides from Salmonella minnesota and Escherichia coli.
- Structure of the core oligosaccharide from lipopolysaccharide of Erwinia carotovora.