AB_(5)-type toxins are a group of secreted protein toxins that are central virulence factors for bacterial pathogens such as Shigella dysenteriae,Vibrio cholerae,Bordetella pertussis,and certain lineages of pathogenic...AB_(5)-type toxins are a group of secreted protein toxins that are central virulence factors for bacterial pathogens such as Shigella dysenteriae,Vibrio cholerae,Bordetella pertussis,and certain lineages of pathogenic Escherichia coli and Salmonella enterica.AB_(5) toxins are composed of an active(A)subunit that manipulates host cell biology in complex with a pentameric binding/delivery(B)subunit that mediates the toxin’s entry into host cells and its subsequent intracellular trafficking.Broadly speaking,all known AB_(5)-type toxins adopt similar structural architectures and employ similar mechanisms of binding,entering and trafficking within host cells.Despite this,there is a remarkable amount of diversity amongst AB_(5)-type toxins;this includes different toxin families with unrelated activities,as well as variation within families that can have profound functional consequences.In this review,we discuss the diversity that exists amongst characterized AB_(5)-type toxins,with an emphasis on the genetic and functional variability within AB_(5) toxin families,how this may have evolved,and its impact on human disease.展开更多
基金supported by a start-up grant provided by the Uni-versity of Alberta Faculty of Science(to C.C.F.)a Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery Grant(Grant number:RGPIN-2020-03964 to C.C.F.).
文摘AB_(5)-type toxins are a group of secreted protein toxins that are central virulence factors for bacterial pathogens such as Shigella dysenteriae,Vibrio cholerae,Bordetella pertussis,and certain lineages of pathogenic Escherichia coli and Salmonella enterica.AB_(5) toxins are composed of an active(A)subunit that manipulates host cell biology in complex with a pentameric binding/delivery(B)subunit that mediates the toxin’s entry into host cells and its subsequent intracellular trafficking.Broadly speaking,all known AB_(5)-type toxins adopt similar structural architectures and employ similar mechanisms of binding,entering and trafficking within host cells.Despite this,there is a remarkable amount of diversity amongst AB_(5)-type toxins;this includes different toxin families with unrelated activities,as well as variation within families that can have profound functional consequences.In this review,we discuss the diversity that exists amongst characterized AB_(5)-type toxins,with an emphasis on the genetic and functional variability within AB_(5) toxin families,how this may have evolved,and its impact on human disease.