1887

Abstract

Accumulating evidence from a number of studies strongly suggests that proteins orthologous to those involved in type IV pili (Tfp) assembly and function are required for pathogenicity. However, the molecular mechanisms by which the components exert their influence on virulence remain poorly understood. Owing to the conservation and promiscuity of Tfp biogenesis machineries, expression of Tfp pilins in heterologous species has been used successfully to analyse organelle structure–function relationships. In this study we expressed a number of pilin genes in the Tfp-expressing pathogen lacking its endogenous pilin subunit. Two gene products, the orthologous PilA proteins from subspecies and , were capable of restoring the expression of Tfp-like appendages that were shown to be dependent upon the neisserial Tfp biogenesis machinery for surface localization. Expression of PilA pilins also partially restored competence for natural transformation in . This phenotype was not complemented by expression of the PulG and XcpT proteins, which are equivalent components of the related type II protein secretion system. Taken together, these findings provide compelling, although indirect, evidence of the potential for PilA proteins to express functional Tfp.

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2009-08-01
2019-09-22
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Primers used in this study [ PDF] (296 kb) Indirect immunofluorescence microscopy (IFM) of expressing different pilin genes from in a background [ PDF] (679 kb) Transmission electron microscopy (TEM) of expressing different pilin genes from in a background [ PDF] (3.45 Mb) Analysis of type II secretion protein PulG and XcpT expression in [ PDF] (564 kb) Detection of pilus structures in different Tfp assembly and biogenesis mutants of expressing PilAFt and PilAFn using indirect immunofluorescence [ PDF] (356 kb)

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Primers used in this study [ PDF] (296 kb) Indirect immunofluorescence microscopy (IFM) of expressing different pilin genes from in a background [ PDF] (679 kb) Transmission electron microscopy (TEM) of expressing different pilin genes from in a background [ PDF] (3.45 Mb) Analysis of type II secretion protein PulG and XcpT expression in [ PDF] (564 kb) Detection of pilus structures in different Tfp assembly and biogenesis mutants of expressing PilAFt and PilAFn using indirect immunofluorescence [ PDF] (356 kb)

PDF

Primers used in this study [ PDF] (296 kb) Indirect immunofluorescence microscopy (IFM) of expressing different pilin genes from in a background [ PDF] (679 kb) Transmission electron microscopy (TEM) of expressing different pilin genes from in a background [ PDF] (3.45 Mb) Analysis of type II secretion protein PulG and XcpT expression in [ PDF] (564 kb) Detection of pilus structures in different Tfp assembly and biogenesis mutants of expressing PilAFt and PilAFn using indirect immunofluorescence [ PDF] (356 kb)

PDF

Primers used in this study [ PDF] (296 kb) Indirect immunofluorescence microscopy (IFM) of expressing different pilin genes from in a background [ PDF] (679 kb) Transmission electron microscopy (TEM) of expressing different pilin genes from in a background [ PDF] (3.45 Mb) Analysis of type II secretion protein PulG and XcpT expression in [ PDF] (564 kb) Detection of pilus structures in different Tfp assembly and biogenesis mutants of expressing PilAFt and PilAFn using indirect immunofluorescence [ PDF] (356 kb)

PDF

Primers used in this study [ PDF] (296 kb) Indirect immunofluorescence microscopy (IFM) of expressing different pilin genes from in a background [ PDF] (679 kb) Transmission electron microscopy (TEM) of expressing different pilin genes from in a background [ PDF] (3.45 Mb) Analysis of type II secretion protein PulG and XcpT expression in [ PDF] (564 kb) Detection of pilus structures in different Tfp assembly and biogenesis mutants of expressing PilAFt and PilAFn using indirect immunofluorescence [ PDF] (356 kb)

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