Mapping of the binding site for Mannheimia haemolytica leukotoxin within bovine CD18.
نویسندگان
چکیده
To map the site involved in Mannheimia haemolytica leukotoxin (LktA) binding and biological activity within bovine CD18, bovine x human CD18 chimeric constructs were generated and coexpressed with bovine CD11a in K562 cells. Studies with the chimeric leukocyte function-associated antigen 1 transductants demonstrate that the site required for LktA binding and biological effects resides within amino acid residues 500 and 600 of the extracellular region of bovine CD18.
منابع مشابه
Intact signal peptide of CD18, the -subunit of 2-integrins, renders ruminants susceptible to Mannheimia haemolytica leukotoxin
Signal peptides of membrane proteins are cleaved by endoplasmic reticulum-resident signal peptidase, and thus, are not present on mature membrane proteins. Here, we report that, contrary to the paradigm, the signal peptide of ruminant CD18, the -subunit of 2-integrins, is not cleaved. Intriguingly, the intact signal peptide of CD18 is responsible for the susceptibility of ruminant leukocytes to...
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Mannheimia (Pasteurella) haemolytica A1 produces several virulence factors that play an important role in the pathogenesis of bovine pneumonic pasteurellosis. Foremost among these is a leukotoxin (LKT) that specifically kills ruminant leukocytes. Recent evidence suggests that M. haemolytica LKT binding to bovine leukocytes is mediated by the beta(2)-integrin CD11a/CD18 (lymphocyte function-asso...
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The leukotoxin (LktA) produced by Mannheimia haemolytica binds to bovine lymphocyte function-associated antigen 1 (LFA-1) and induces biological effects in bovine leukocytes in a cellular and species-specific fashion. We have previously shown that LktA also binds to porcine LFA-1 without eliciting any effects. These findings suggest that the specificity of LktA effects must entail both binding ...
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ورودعنوان ژورنال:
- Infection and immunity
دوره 73 8 شماره
صفحات -
تاریخ انتشار 2005