Related Experiment Video
Updated: Dec 11, 2025
08:44
Visualization of Twitching Motility and Characterization of the Role of the PilG in Xylella fastidiosa
Published on: April 8, 2016
11.2K
Biogenesis of Type V pili.
Mikio Shoji1, Satoshi Shibata2, Takayuki Sueyoshi1
1Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Nagasaki, Japan.
Microbiology and Immunology
|August 21, 2020
Summary
Porphyromonas gingivalis pili, known as Type V pili, assemble via a novel protease-mediated mechanism. This study details their unique transport and assembly, distinct from other bacterial pili.
Area of Science:
- Microbiology
- Structural Biology
- Bacteriology
Background:
- Pili (fimbriae) are bacterial surface filaments.
- Porphyromonas gingivalis pili (Fim pili) have unique characteristics, including a larger stalk pilin (FimA).
- Previous work indicated FimA secretion as a lipoprotein precursor requiring protease processing for pilus formation.
Purpose of the Study:
- To elucidate the novel assembly and transport mechanisms of P. gingivalis Type V pili.
- To provide structural insights into Fim pili formation.
- To describe lipoprotein transport in Gram-negative bacteria.
Main Methods:
- Purification of pili from Porphyromonas gingivalis.
- Determination of crystal structures of FimA and related proteins.
- Cryoelectron microscopy of pilus structure.
Main Results:
- P. gingivalis Fim pili are formed via a protease-mediated strand-exchange mechanism.
- Cryo-EM data support this novel assembly pathway.
- Type V pili assembly differs significantly from other known pili.
- Surface lipoproteins like FimB are involved in Fim pili anchoring.
Conclusions:
- P. gingivalis Fim pili represent a distinct class, designated Type V pili, due to their unique assembly and transport mechanisms.
- Protease activity is crucial for Fim pili formation.
- Understanding these mechanisms offers insights into bacterial surface structure assembly and lipoprotein transport.
More Related Videos
09:05High Resolution Electron Microscopy of the Helicobacter pylori Cag Type IV Secretion System Pili Produced in Varying Conditions of Iron Availability
Published on: November 21, 2014
15.7K
12:29Generation of Null Mutants to Elucidate the Role of Bacterial Glycosyltransferases in Bacterial Motility
Published on: March 11, 2022
2.6K
Related Concept Videos
01:28Fimbriae, Pili, and Axial Filaments
1.2K
Fimbriae and pili are specialized bacterial surface structures that play pivotal roles in adhesion, genetic exchange, and motility. Composed primarily of pilin protein, these hairlike appendages are crucial for bacterial survival and pathogenicity in various environments.Fimbriae: Adhesion and PathogenicityFimbriae are fine, filamentous structures measuring 2–10 nanometers in diameter and are densely distributed on the bacterial cell surface. They facilitate bacterial adhesion to abiotic...
1.2K
01:23Surface Appendages of Archaea
445
Archaeal surface appendages are highly specialized structures essential for environmental adaptation, encompassing roles in adhesion, biofilm formation, and motility. Among these appendages, pili and archaella stand out for their distinct morphologies and functionalities, enabling archaea to thrive in diverse and often extreme environments.Pili: Adhesion and Biofilm FormationPili are filamentous structures assembled from pilin protein subunits, primarily contributing to adhesion and biofilm...
445
01:39Mechanism of Filopodia Formation
2.9K
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
2.9K
01:19Mechanism of Conjugation
570
Bacterial conjugation is a mechanism of horizontal gene transfer that enables the exchange of genetic material between bacterial cells through direct contact. This process is facilitated by a donor cell carrying a conjugative plasmid, which encodes genes necessary for pilus formation, DNA replication, and transfer. The conjugative plasmid plays a central role in initiating and executing the transfer of genetic material.The tra region of the conjugative plasmid encodes proteins responsible for...
570
01:29Cytoskeletal Proteins in Bacteria
4.0K
Bacterial cells were initially considered simple, randomly organized structures lacking a cytoskeleton. However, the discovery of cytoskeleton homologs in bacteria led to the change of this opinion. Bacterial cytoskeletal filaments regulate the cell shape, cell polarity, cell division, and partitioning of plasmids during cell division. It was later discovered that bacterial cytoskeletal proteins, mainly actin and tubulin homologs, are diverse compared to their eukaryotic counterparts. On the...
4.0K
01:31Types of Intermediate Filaments
4.5K
The intermediate filaments are an essential component of the cytoskeleton. Presently six types of intermediate filament have been identified. Type I and II are acidic and basic keratin proteins. Type III is of mesodermal origin and comprises four proteins: vimentin, desmin, glial fibrillary acidic protein (GFAP), and peripherin. Vimentin is commonly found in mesenchymal cells, desmin in muscle cells, GFAP in astrocytes, while peripherin is found in peripheral nervous system neurons (PNS). Type...
4.5K