Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Reversible adhesion by type IV pili leads to formation of permanent localized clusters

ABSTRACT: Summary The formation of long-lived, multicellular clusters is a fundamental step in the physiopathology of many disease-causing bacteria. Experiments on abiotic surfaces suggest that bacterial colonization, including initial cluster formation, requires (1) irreversible adhesion, (2) cell proliferation, and (3) a phenotypic transition. However, here we show that on infection of a polarized MDCK epithelium, Pseudomonas aeruginosa (PA) forms long-lived – i.e., permanent – bacterial clusters without requiring irreversible adhesion, cell proliferation, or a phenotypic transition. By combining experiments and a mathematical model, we reveal that the cluster formation process is mediated by type IV pili (T4P). Furthermore, we unveil how T4P quantitatively operate during adhesion, finding that it is a stochastic process that involves an activation time, requires the retraction of pili, and results in reversible attachment. We explain how such reversible attachment process leads to the formation of permanent bacterial clusters and quantify the cluster growth dynamics. Graphical abstract Highlights • P. aeruginosa adheres to apoptotic cells through a functional type-four pili• P. aeruginosa preferentially adheres to vesiculated apoptotic membranes• The formation of stable bacterial clusters does not require irreversible adhesion Microbiology; Cell biology; Mathematical biosciences

SUBMITTER: Pepe M

PROVIDER: S-EPMC9700013 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Nanoscale adhesion forces of Pseudomonas aeruginosa type IV Pili.

Project description:A variety of bacterial pathogens use nanoscale protein fibers called type IV pili to mediate cell adhesion, a primary step leading to infection. Currently, how these nanofibers respond to mechanical stimuli and how this response is used to control adhesion is poorly understood. Here, we use atomic force microscopy techniques to quantify the forces guiding the adhesion of Pseudomonas aeruginosa type IV pili to surfaces. Using chemical force microscopy and single-cell force spectroscopy, we show that pili strongly bind to hydrophobic surfaces in a time-dependent manner, while they weakly bind to hydrophilic surfaces. Individual nanofibers are capable of withstanding forces up to 250 pN, thereby explaining how they can resist mechanical stress. Pulling on individual pili yields constant force plateaus, presumably reflecting conformational changes, as well as nanospring properties that may help bacteria to withstand physiological shear forces. Analysis of mutant strains demonstrates that these mechanical responses originate solely from type IV pili, while flagella and the cell surface localized and proposed pili-associated adhesin PilY1 play no direct role. We also demonstrate that bacterial-host interactions involve constant force plateaus, the extension of bacterial pili, and the formation of membrane tethers from host cells. We postulate that the unique mechanical responses of type IV pili unravelled here enable the bacteria to firmly attach to biotic and abiotic surfaces and thus maintain attachment when subjected to high shear forces under physiological conditions, helping to explain why pili play a critical role in colonization of the host.

| S-EPMC4212785 | biostudies-other

Characterization of adhesion threads of Deinococcus geothermalis as type IV pili.

Project description:Deinococcus geothermalis E50051 forms tenuous biofilms on paper machine surfaces. Field emission electron microscopy analysis revealed peritrichous appendages which mediated cell-to-surface and cell-to-cell interactions but were absent in planktonically grown cells. The major protein component of the extracellular extract of D. geothermalis had an N-terminal sequence similar to the fimbrial protein pilin annotated in the D. geothermalis DSM 11300 draft sequence. It also showed similarity to the type IV pilin sequence of D. radiodurans and several gram-negative pathogenic bacteria. Other proteins in the extract had N-terminal sequences identical to D. geothermalis proteins with conservative motifs for serine proteases, metallophosphoesterases, and proteins whose function is unknown. Periodic acid-Schiff staining for carbohydrates indicated that these extracellular proteins may be glycosylated. A further confirmation for the presence of glycoconjugates on the cell surface was obtained by confocal laser scanning imaging of living D. geothermalis cells stained with Amaranthus caudatus lectin, which specifically binds to galactose residues. The results indicate that the thread-like appendages of D. geothermalis E50051 are glycosylated type IV pili, bacterial attachment organelles which have thus far not been described for the genus Deinococcus.

| S-EPMC1595522 | biostudies-literature

Motility and adhesion through type IV pili in Gram-positive bacteria.

Project description:Type IV pili are hair-like bacterial surface appendages that play a role in diverse processes such as cellular adhesion, colonization, twitching motility, biofilm formation, and horizontal gene transfer. These extracellular fibers are composed exclusively or primarily of many copies of one or more pilin proteins, tightly packed in a helix so that the highly hydrophobic amino-terminus of the pilin is buried in the pilus core. Type IV pili have been characterized extensively in Gram-negative bacteria, and recent advances in high-throughput genomic sequencing have revealed that they are also widespread in Gram-positive bacteria. Here, we review the current state of knowledge of type IV pilus systems in Gram-positive bacterial species and discuss them in the broader context of eubacterial type IV pili.

| S-EPMC5830096 | biostudies-literature

Type IV pili promote early biofilm formation by Clostridium difficile

Project description:Transcriptional analysis of Clostridium difficile R20291 in biofilm formation, planktonic state and grown on blood agar

2016-05-18 | GSE69001 | GEO

Type IV pili promote early biofilm formation by Clostridium difficile.

Project description:Increasing morbidity and mortality from Clostridium difficile infection (CDI) present an enormous challenge to healthcare systems. Clostridium difficile express type IV pili (T4P), but their function remains unclear. Many chronic and recurrent bacterial infections result from biofilms, surface-associated bacterial communities embedded in an extracellular matrix. CDI may be biofilm mediated; T4P are important for biofilm formation in a number of organisms. We evaluate the role of T4P in C. difficile biofilm formation using RNA sequencing, mutagenesis and complementation of the gene encoding the major pilin pilA1, and microscopy. RNA sequencing demonstrates that, in comparison to other growth phenotypes, C. difficile growing in a biofilm has a distinct RNA expression profile, with significant differences in T4P gene expression. Microscopy of T4P-expressing and T4P-deficient strains suggests that T4P play an important role in early biofilm formation. A non-piliated pilA1 mutant forms an initial biofilm of significantly reduced mass and thickness in comparison to the wild type. Complementation of the pilA1 mutant strain leads to formation of a biofilm which resembles the wild-type biofilm. These findings suggest that T4P play an important role in early biofilm formation. Novel strategies for confronting biofilm infections are emerging; our data suggest that similar strategies should be investigated in CDI.

| S-EPMC5985507 | biostudies-literature

Type IV pili promote early biofilm formation by Clostridium difficile

Project description:Transcriptional analysis of Clostridium difficile R20291 in biofilm formation, planktonic state and grown on blood agar RNA sequencing was performed on Clostridium difficile R20291 in three different conditions: Biofilm formation, plantonic state and grown on blood agar plates. Each condtion has 3 replicates.

2016-05-18 | E-GEOD-69001 | biostudies-arrayexpress

Nanoscale Pulling of Type IV Pili Reveals Their Flexibility and Adhesion to Surfaces over Extended Lengths of the Pili.

Project description:Type IV pili (T4P) are very thin protein filaments that extend from and retract into bacterial cells, allowing them to interact with and colonize a broad array of chemically diverse surfaces. The physical aspects that allow T4P to mediate adherence to many different surfaces remain unclear. Atomic force microscopy (AFM) nanoscale pulling experiments were used to measure the mechanical properties of T4P of a mutant strain of Pseudomonas aeruginosa PAO1 unable to retract its T4P. After adhering bacteria to the end of an AFM cantilever and approaching surfaces of mica, gold, or polystyrene, we observed adhesion of the T4P to all of the surfaces. Pulling of single and multiple T4P on retraction of the cantilever from the surfaces could be described using the worm-like chain (WLC) model. Distinct peaks in the measured distributions of the best-fit values of the persistence length Lp on two different surfaces provide strong evidence for close-packed bundling of very flexible T4P. In addition, we observed force plateaus indicating that adhesion of the T4P to both hydrophilic and hydrophobic surfaces occurs along extended lengths of the T4P. These data shed new light, to our knowledge, on T4P flexibility and support a low-affinity, high-avidity adhesion mechanism that mediates bacteria-surface interactions.

| S-EPMC4472224 | biostudies-literature

Recognition of extracellular DNA by type IV pili promotes biofilm formation by Clostridioides difficile.

Project description:Clostridioides difficile is a Gram-positive bacillus, which is a frequent cause of gastrointestinal infections triggered by the depletion of the gut microbiome. Because of the frequent recurrence of these infections after antibiotic treatment, mechanisms of C. difficile persistence and recurrence, including biofilm formation, are of increasing interest. Previously, our group and others found that type IV pili, filamentous helical appendages polymerized from protein subunits, promoted microcolony and biofilm formation in C. difficile. In Gram-negative bacteria, the ability of type IV pili to mediate bacterial self-association has been explained through interactions between the pili of adjacent cells, but type IV pili from several Gram-negative species are also required for natural competence through DNA uptake. Here, we report the ability of two C. difficile pilin subunits, PilJ and PilW, to bind to DNA in vitro, as well as the defects in biofilm formation in the pilJ and pilW gene-interruption mutants. Additionally, we have resolved the X-ray crystal structure of PilW, which we use to model possible structural mechanisms for the formation of C. difficile biofilm through interactions between type IV pili and the DNA of the extracellular matrix. Taken together, our results provide further insight into the relationship between type IV pilus function and biofilm formation in C. difficile and, more broadly, suggest that DNA recognition by type IV pili and related structures may have functional importance beyond DNA uptake for natural competence.

| S-EPMC9556784 | biostudies-literature

Type IV pili in Gram-positive bacteria.

Project description:Type IV pili (T4P) are surface-exposed fibers that mediate many functions in bacteria, including locomotion, adherence to host cells, DNA uptake (competence), and protein secretion and that can act as nanowires carrying electric current. T4P are composed of a polymerized protein, pilin, and their assembly apparatuses share protein homologs with type II secretion systems in eubacteria and the flagella of archaea. T4P are found throughout Gram-negative bacterial families and have been studied most extensively in certain model Gram-negative species. Recently, it was discovered that T4P systems are also widespread among Gram-positive species, in particular the clostridia. Since Gram-positive and Gram-negative bacteria have many differences in cell wall architecture and other features, it is remarkable how similar the T4P core proteins are between these organisms, yet there are many key and interesting differences to be found as well. In this review, we compare the two T4P systems and identify and discuss the features they have in common and where they differ to provide a very broad-based view of T4P systems across all eubacterial species.

| S-EPMC3811610 | biostudies-literature

Purification and characterization of thin pili of IncI1 plasmids ColIb-P9 and R64: formation of PilV-specific cell aggregates by type IV pili.

Project description:Thin pili of the closely related IncI1 plasmids ColIb-P9 and R64 are required only for liquid mating and belong to the type IV family of pili. They were sedimented by ultracentrifugation from culture medium in which Escherichia coli cells harboring ColIb-P9- or R64-derived plasmids had been grown, and then the pili were purified by CsCl density gradient centrifugation. In negatively stained thin pilus samples, long rods with a diameter of 6 nm, characteristic of type IV pili, were observed under an electron microscope. Gel electrophoretic analysis of purified ColIb-P9 thin pili indicated that thin pili consist of two kinds of proteins, pilin and the PilV protein. Pilin was demonstrated to be the product of the pilS gene. Pilin was first synthesized as a 22-kDa prepilin from the pilS gene and subsequently processed to a 19-kDa protein by the function of the pilU product. The N-terminal amino group of the processed protein was shown to be modified. The C-terminal segments of the pilV products vary among six or seven different types, as a result of shufflon DNA rearrangements of the pilV gene. These PilV proteins were revealed to comprise a minor component of thin pili. Formation of PilV-specific cell aggregates by ColIb-P9 and R64 thin pili was demonstrated and may play an important role in liquid mating.

| S-EPMC107247 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data