Phenotypic characterization of a virulence-associated protein, VagH, of Yersinia pseudotuberculosis reveals a tight link between VagH and the type III secretion system

Methylation and in vivo expression of the surface-exposed Leptospira interrogans outer-membrane protein OmpL32

“…The Y. pseudotuberculosis vagH insertion mutant demonstrated repression of secretion of the virulence determinant YopD via the type III secretion system (Garbom et al, 2007). Additionally, this mutant displayed characteristics similar to a type III secretion mutant during pathogenesis, suggesting a role for protein methylation in type III secretion function (Garbom et al, 2007). Within the context of outermembrane protein methylation and bacterial pathogenesis, a link has been demonstrated in the bacterial pathogen R. prowazekii.…”

“…A requirement for methylation has been demonstrated in Y. pseudotuberculosis, where an insertion mutant deficient in the VagH protein is avirulent in mice (Garbom et al, 2004). In Y. pseudotuberculosis, the VagH protein is homologous to the E. coli HemK protein (Garbom et al, 2007), an N 5 -methyltransferase (Heurgué-Hamard et al, 2002;Nakahigashi et al, 2002). The Y. pseudotuberculosis vagH insertion mutant demonstrated repression of secretion of the virulence determinant YopD via the type III secretion system (Garbom et al, 2007).…”

“…First, methylation could potentially be used by bacteria to regulate protein function, in a manner analogous to that seen for chemotaxis proteins (Wadhams & Armitage, 2004) and the Y. pseudotuberculosis type III secretion system (Garbom et al, 2007). In this scenario, methylation could act to regulate the function of leptospiral virulence factors present on the spirochaetal surface by providing a post-translationally controlled switch between an active/inactive state, and in this way ensure optimal timing of virulence protein function within the infection process.…”

“…In Y. pseudotuberculosis, the VagH protein is homologous to the E. coli HemK protein (Garbom et al, 2007), an N 5 -methyltransferase (Heurgué-Hamard et al, 2002;Nakahigashi et al, 2002). The Y. pseudotuberculosis vagH insertion mutant demonstrated repression of secretion of the virulence determinant YopD via the type III secretion system (Garbom et al, 2007). Additionally, this mutant displayed characteristics similar to a type III secretion mutant during pathogenesis, suggesting a role for protein methylation in type III secretion function (Garbom et al, 2007).…”

“…Methylation of glycolipids has been shown to be essential for Mycobacterium avium virulence in mice (Krzywinska et al, 2005), while methylation of proteins has been shown to alter the antigenicity of the outer-membrane protein OmpB from Rickettsia typhi (Chao et al, 2008), and to alter both the antigenicity of and the host T cell-mediated immune response against the heparin-binding haemagglutinin from Mycobacterium tuberculosis Temmerman et al, 2004). In addition, methylation has been demonstrated to be essential for functional type III secretion, and thus virulence, in Yersinia pseudotuberculosis (Garbom et al, 2004(Garbom et al, , 2007, and methylation of the surface protein OmpB in Rickettsia prowazaki has been suggested to be central to the pathogenesis of that bacterium (Chao et al, 2004(Chao et al, , 2007. Collectively, these investigations highlight the importance of methylation of outer-membrane surface components in bacterial virulence.…”