Distribution and Phylogeny of Immunoglobulin-Binding Protein G in Shiga Toxin-Producing Escherichia coli and Its Association with Adherence Phenotypes

Autor: Angelika Fruth, Johannes Müthing, Barbara Middendorf, Viktor Merkel, Christian Menge, Barbara Ohder, Erika Borrmann, Helge Karch, Martina Bielaszewska, Alexander Mellmann, Wenlan Zhang
Rok vydání: 2010
Předmět:
Zdroj: Infection and Immunity. 78:3625-3636
ISSN: 1098-5522
0019-9567
Popis: eibG in Shiga toxin-producing Escherichia coli (STEC) O91 encodes a protein (EibG) which binds human immunoglobulins G and A and contributes to bacterial chain-like adherence to human epithelial cells. We investigated the prevalence of eibG among STEC, the phylogeny of eibG , and eibG allelic variations and their impact on the adherence phenotype. eibG was found in 15.0% of 240 eae -negative STEC strains but in none of 157 eae -positive STEC strains. The 36 eibG -positive STEC strains belonged to 14 serotypes and to eight multilocus sequence types (STs), with serotype O91:H14/H − and ST33 being the most common. Sequences of the complete eibG gene (1,527 bp in size) from eibG -positive STEC resulted in 21 different alleles with 88.11% to 100% identity to the previously reported eibG sequence; they clustered into three eibG subtypes ( eibG -α, eibG -β, and eibG -γ). Strains expressing EibG-α and EibG-β displayed a mostly typical chain-like adherence pattern (CLAP), with formation of long chains on both human and bovine intestinal epithelial cells, whereas strains with EibG-γ adhered in short chains, a pattern we termed atypical CLAP. The same adherence phenotypes were displayed by E. coli BL21(DE3) clones containing the respective eibG -α, eibG -β, and eibG- γ subtypes. We propose two possible evolutionary scenarios for eibG in STEC: a clonal development of eibG in strains with the same phylogenetic background or horizontal transfer of eibG between phylogenetically unrelated STEC strains.
Databáze: OpenAIRE