Competitive Substrate Binding Coordinates the Two Antagonistic Motors of the Bacterial Type IV Pilus

Bacterial type IV secretion systems (T4SS) perform two fundamental functions related to pathogenesis: the delivery of effector molecules to eukaryotic target cells, and genetic exchange. Two T4SSs have been identified in Burkholderia cenocepacia K56-2, a representative of the ET12 lineage of the B. cepacia complex (Bcc). The plant tissue watersoaking (Ptw) T4SS encoded on a resident 92 kb plasmid is a chimera composed of VirB/D4 and F-specific subunits, and is responsible for the translocation of effector(s) that have been linked to the Ptw phenotype. The bc-VirB/D4 system located on chromosome II displays homology to the VirB/D4 T4SS of Agrobacterium tumefaciens. In contrast to the Ptw T4SS, the bc-VirB/D4 T4SS was found to be dispensable for Ptw effector(s) secretion, but was found to be involved in plasmid mobilization. The fertility inhibitor Osa did not affect the secretion of Ptw effector(s) via the Ptw system, but did disrupt the mobilization of a RSF1010 derivative plasmid.

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Disarming Bacterial Type IV Secretion

Chemistry & Biology ◽

10.1016/j.chembiol.2012.08.002 ◽

2012 ◽

Vol 19 (8) ◽

pp. 934-936 ◽

Cited By ~ 3

Author(s):

Todd A. Cameron ◽

Patricia C. Zambryski

Keyword(s):

Type Iv Secretion ◽

Type Iv ◽

Bacterial Type

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Type IV Pilus Assembly Proficiency and Dynamics Influence Pilin Subunit Phospho-Form Macro- and Microheterogeneity in Neisseria gonorrhoeae

PLoS ONE ◽

10.1371/journal.pone.0096419 ◽

2014 ◽

Vol 9 (5) ◽

pp. e96419 ◽

Cited By ~ 1

Author(s):

Åshild Vik ◽

Jan Haug Anonsen ◽

Finn Erik Aas ◽

Finn Terje Hegge ◽

Norbert Roos ◽

...

Keyword(s):

Neisseria Gonorrhoeae ◽

Type Iv Pilus ◽

Type Iv ◽

Pilin Subunit ◽

Pilus Assembly

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Identification and initial characterization of a new pair of sibling sRNAs of Neisseria gonorrhoeae involved in type IV pilus biogenesis

Microbiology ◽

10.1099/mic.0.001080 ◽

2021 ◽

Vol 167 (9) ◽

Author(s):

Marie Zachary ◽

Susanne Bauer ◽

Maximilian Klepsch ◽

Katharina Wagler ◽

Bruno Hüttel ◽

...

Keyword(s):

Target Genes ◽

Target Prediction ◽

Type Iv Pilus ◽

Content Type ◽

Type Iv ◽

Gene Expression Control ◽

Initial Characterization ◽

Pilus Biogenesis ◽

Regulatory Rnas

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.

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Purification and Three-Dimensional Electron Microscopy Structure of the Neisseria meningitidis Type IV Pilus Biogenesis Protein PilG

Journal of Bacteriology ◽

10.1128/jb.00648-07 ◽

2007 ◽

Vol 189 (17) ◽

pp. 6389-6396 ◽

Cited By ~ 25

Author(s):

Richard F. Collins ◽

Muhammad Saleem ◽

Jeremy P. Derrick

Keyword(s):

Electron Microscopy ◽

Neisseria Meningitidis ◽

Metal Ion ◽

Polyacrylamide Gel Electrophoresis ◽

Three Dimensional ◽

Type Ii Secretion ◽

Type Ii ◽

Type Iv Pilus ◽

Type Iv ◽

Pilus Biogenesis

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.

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