Functional analyses of pilin-like proteins from Francisella tularensis : complementation of type IV pilus phenotypes in Neisseria gonorrhoeae

• 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 Francisella 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 Francisella pilin genes in the Tfp-expressing pathogen Neisseria gonorrhoeae lacking its endogenous pilin subunit. Two gene products, the orthologous PiIA proteins from Francisella tularensis subspecies tularensis and novicida, 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 Francisella PiIA pilins also partially restored competence for natural transformation in N. gonorrhoeae. This phenotype was not complemented by expression of the PuIG 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 Francisella PiIA proteins to express functional Tfp.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Mikrobiologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Microbiology in the medical area (hsv//eng)

Nyckelord

IFM

immunofluorescence microscopy

TEM

transmission electron microscopy

DATDH

2

4-diacetamido-2

4

6-trideoxyhexose

SOEing PCR

splicing by overlapping extension PCR

LVS

live vaccine strain

T2SS

type II secretion system

Tfp

type IV pili

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)