Pilus biogenesis by the chaperone-usher pathway.

Author(s):  
G. Phan ◽  
G. Waksman
Keyword(s):  
1994 ◽  
Vol 269 (16) ◽  
pp. 12233-12239
Author(s):  
R. Striker ◽  
F. Jacob-Dubuisson ◽  
C. Freiden ◽  
S.J. Hultgren
Keyword(s):  

Microbiology ◽  
2021 ◽  
Vol 167 (9) ◽  
Author(s):  
Marie Zachary ◽  
Susanne Bauer ◽  
Maximilian Klepsch ◽  
Katharina Wagler ◽  
Bruno Hüttel ◽  
...  

Non-coding regulatory RNAs mediate post-transcriptional gene expression control by a variety of mechanisms relying mostly on base-pairing interactions with a target mRNA. Though a plethora of putative non-coding regulatory RNAs have been identified by global transcriptome analysis, knowledge about riboregulation in the pathogenic Neisseriae is still limited. Here we report the initial characterization of a pair of sRNAs of N. gonorrhoeae , TfpR1 and TfpR2, which exhibit a similar secondary structure and identical single-stranded seed regions, and therefore might be considered as sibling sRNAs. By combination of in silico target prediction and sRNA pulse expression followed by differential RNA sequencing we identified target genes of TfpR1 which are involved in type IV pilus biogenesis and DNA damage repair. We provide evidence that members of the TfpR1 regulon can also be targeted by the sibling TfpR2.


2007 ◽  
Vol 189 (17) ◽  
pp. 6389-6396 ◽  
Author(s):  
Richard F. Collins ◽  
Muhammad Saleem ◽  
Jeremy P. Derrick

ABSTRACT Type IV pili are surface-exposed retractable fibers which play a key role in the pathogenesis of Neisseria meningitidis and other gram-negative pathogens. PilG is an integral inner membrane protein and a component of the type IV pilus biogenesis system. It is related by sequence to the extensive GspF family of secretory proteins, which are involved in type II secretion processes. PilG was overexpressed and purified from Escherichia coli membranes by detergent extraction and metal ion affinity chromatography. Analysis of the purified protein by perfluoro-octanoic acid polyacrylamide gel electrophoresis showed that PilG formed dimers and tetramers. A three-dimensional (3-D) electron microscopy structure of the PilG multimer was determined using single-particle averaging applied to samples visualized by negative staining. Symmetry analysis of the unsymmetrized 3-D volume provided further evidence that the PilG multimer is a tetramer. The reconstruction also revealed an asymmetric bilobed structure approximately 125 Å in length and 80 Å in width. The larger lobe within the structure was identified as the N terminus by location of Ni-nitrilotriacetic acid nanogold particles to the N-terminal polyhistidine tag. We propose that the smaller lobe corresponds to the periplasmic domain of the protein, with the narrower “waist” region being the transmembrane section. This constitutes the first report of a 3-D structure of a member of the GspF family and suggests a physical basis for the role of the protein in linking cytoplasmic and periplasmic protein components of the type II secretion and type IV pilus biogenesis systems.


PLoS ONE ◽  
2012 ◽  
Vol 7 (12) ◽  
pp. e50989 ◽  
Author(s):  
Virginie Oxaran ◽  
Florence Ledue-Clier ◽  
Yakhya Dieye ◽  
Jean-Marie Herry ◽  
Christine Péchoux ◽  
...  

2015 ◽  
Vol 11 (11) ◽  
pp. e1005269 ◽  
Author(s):  
Natalia Pakharukova ◽  
James A. Garnett ◽  
Minna Tuittila ◽  
Sari Paavilainen ◽  
Mamou Diallo ◽  
...  

2009 ◽  
Vol 71 (3) ◽  
pp. 779-794 ◽  
Author(s):  
Simon J. Jakubowski ◽  
Jennifer E. Kerr ◽  
Isaac Garza ◽  
Vidhya Krishnamoorthy ◽  
Richard Bayliss ◽  
...  

2019 ◽  
Vol 116 (28) ◽  
pp. 14222-14227 ◽  
Author(s):  
Bo Hu ◽  
Pratick Khara ◽  
Peter J. Christie

Bacterial conjugation systems are members of the large type IV secretion system (T4SS) superfamily. Conjugative transfer of F plasmids residing in theEnterobacteriaceaewas first reported in the 1940s, yet the architecture of F plasmid-encoded transfer channel and its physical relationship with the F pilus remain unknown. We visualized F-encoded structures in the native bacterial cell envelope by in situ cryoelectron tomography (CryoET). Remarkably, F plasmids encode four distinct structures, not just the translocation channel or channel-pilus complex predicted by prevailing models. The F1 structure is composed of distinct outer and inner membrane complexes and a connecting cylinder that together house the envelope-spanning translocation channel. The F2 structure is essentially the F1 complex with the F pilus attached at the outer membrane (OM). Remarkably, the F3 structure consists of the F pilus attached to a thin, cell envelope-spanning stalk, whereas the F4 structure consists of the pilus docked to the OM without an associated periplasmic density. The traffic ATPase TraC is configured as a hexamer of dimers at the cytoplasmic faces of the F1 and F2 structures, where it respectively regulates substrate transfer and F pilus biogenesis. Together, our findings present architectural renderings of the DNA conjugation or “mating” channel, the channel–pilus connection, and unprecedented pilus basal structures. These structural snapshots support a model for biogenesis of the F transfer system and allow for detailed comparisons with other structurally characterized T4SSs.


Sign in / Sign up

Export Citation Format

Share Document