Mechanism of assembly of type 4 filaments: everything you always wanted to know (but were afraid to ask)

Microbiology, Год журнала: 2023, Номер 169(3)

Опубликована: Март 22, 2023

Type 4 filaments (T4F) are a superfamily of filamentous nanomachines – virtually ubiquitous in prokaryotes and functionally versatile which type pili (T4P) the defining member. T4F polymers pilins, assembled by conserved multi-protein machineries. They have long been an important topic for research because they key virulence factors numerous bacterial pathogens. Our poor understanding molecular mechanisms assembly is serious hindrance to design anti-T4F therapeutics. This review attempts shed light on fundamental mechanistic principles at play focusing similarities rather than differences between several (mostly bacterial) T4F. holistic approach, complemented revolutionary ability artificial intelligence predict protein structures, led intriguing model assembly.

Язык: Английский

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Pseudomonas aeruginosa type IV minor pilins and PilY1 regulate virulence by modulating FimS-AlgR activity

PLoS Pathogens, Год журнала: 2018, Номер 14(5), С. e1007074 - e1007074

Опубликована: Май 18, 2018

Type IV pili are expressed by a wide range of prokaryotes, including the opportunistic pathogen Pseudomonas aeruginosa. These flexible fibres mediate twitching motility, biofilm maturation, surface adhesion, and virulence. The pilus is composed mainly major pilin subunits while low abundance minor pilins FimU-PilVWXE putative adhesin PilY1 prime assembly proposed to form tip. encoded in an operon that positively regulated FimS-AlgR two-component system. Independent assembly, was be mechanosensory component that—in conjunction with pilins—triggers up-regulation acute virulence phenotypes upon attachment. Here, we investigated link between pilins/PilY1 pilW, pilX, pilY1 mutants had reduced towards Caenorhabditis elegans relative wild type or mutant, implying role pathogenicity independent assembly. We hypothesized loss specific relieves feedback inhibition on FimS-AlgR, increasing transcription AlgR regulon delaying C. killing. Reporter assays confirmed were required for increased expression select pilins. Overexpression its hyperactivation via phosphomimetic mutation virulence, defects activation. propose inhibit their own expression, these proteins leads FimS-mediated activation suppresses acute-phase factors delays This mechanism could contribute adaptation P. aeruginosa chronic lung infections, as mutations result piliation AlgR-dependent factors–such alginate–that characteristic such infections.

Язык: Английский

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Architecture, Function, and Substrates of the Type II Secretion System

EcoSal Plus, Год журнала: 2019, Номер 8(2)

Опубликована: Фев. 15, 2019

The type II secretion system (T2SS) delivers toxins and a range of hydrolytic enzymes, including proteases, lipases, carbohydrate-active to the cell surface or extracellular space Gram-negative bacteria. Its contribution survival both intracellular pathogens as well environmental species proteobacteria is evident. This dynamic, multicomponent machinery spans entire envelope consists cytoplasmic ATPase, several inner membrane proteins, periplasmic pseudopilus, secretin pore embedded in outer membrane. Despite trans -envelope configuration T2S nanomachine, proteins be secreted engage with first once they enter compartment via Sec TAT export system. Thus, T2SS specifically dedicated their translocation. many sequence structural similarities between IV pili suggest common origin argue for pilus-mediated mechanism secretion. minireview describes structures, functions, interactions individual components general architecture assembled briefly summarizes transport function growing list exoproteins. Recent advances cryo-electron microscopy, which have led an increased understanding structure-function relationship channel are emphasized.

Язык: Английский

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DNA-uptake pili of Vibrio cholerae are required for chitin colonization and capable of kin recognition via sequence-specific self-interaction

Nature Microbiology, Год журнала: 2019, Номер 4(9), С. 1545 - 1557

Опубликована: Июнь 10, 2019

Язык: Английский

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Tad Pili Play a Dynamic Role in Caulobacter crescentus Surface Colonization

mBio, Год журнала: 2019, Номер 10(3)

Опубликована: Июнь 17, 2019

Bacterial surface attachment is mediated by filamentous appendages called pili. Here, we describe the role of Tad pili during colonization Caulobacter crescentus Using an optical trap and microfluidic controlled flow conditions to mimic natural environments, demonstrated that undergo repeated dynamic cycles extension retraction. Within seconds after establishing contact, pilus retraction reorients cells into upright position, promoting walking-like movements against medium flow. Pilus-mediated positioning flagellate pole close facilitates motor-mediated mechanical sensing promotes anchoring holdfast, adhesive substance affords long-term attachment. We present evidence second messenger c-di-GMP regulates dynamics encounter in distinct ways, increased activity at intermediate levels peak concentrations. propose a model which flagellum functionally interact together impose ratchet-like mechanism progressively drives C. toward permanent attachment.IMPORTANCE Bacteria are able colonize surfaces environmental, industrial, medical settings, where they form resilient communities biofilms. In order control bacterial colonization, microbiologists need gain detailed understanding processes bacteria use live liquid-surface interface allow them adhere move on eventually grow persist solid media. To facilitate these processes, equipped with structures such as flagella matrix components exopolysaccharides. How cellular organelles coordinated optimize currently subject intense investigations. Here used organism demonstrate polar highly interconnected flagellar motor mediate sensing, thereby enforcing rapid These studies provide entry point for in-depth molecular analysis colonization.

Язык: Английский

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PilT and PilU are homohexameric ATPases that coordinate to retract type IVa pili

PLoS Genetics, Год журнала: 2019, Номер 15(10), С. e1008448 - e1008448

Опубликована: Окт. 18, 2019

Bacterial type IV pili are critical for diverse biological processes including horizontal gene transfer, surface sensing, biofilm formation, adherence, motility, and virulence. These dynamic appendages extend retract from the cell surface. In many IVa pilus systems, extension occurs through action of an ATPase, often called PilB, while optimal retraction requires a PilT. Many systems also encode homolog PilT PilU. However, function this protein has remained unclear because pilU mutants exhibit inconsistent phenotypes among it is relatively understudied compared to Here, we study competence Vibrio cholerae as model system define role We show that ATPase activity PilU in Walker A and/or B mutants. does not, however, contribute ΔpilT strains. Thus, these data suggest bona fide supports PilT-dependent manner. found ΔpilU mutant exhibited reduction force suggesting important generating maximal forces. Additional vitro vivo act independent homo-hexamers may form complex facilitate retraction. Finally, demonstrate conserved Acinetobacter baylyi, described here be broadly applicable other systems.

Язык: Английский

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A bifunctional ATPase drives tad pilus extension and retraction

Science Advances, Год журнала: 2019, Номер 5(12)

Опубликована: Дек. 6, 2019

A single ATPase powers extension and retraction of a broadly distributed class type IV pili.

Язык: Английский

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Type IV pili of Enterobacteriaceae species

EcoSal Plus, Год журнала: 2024, Номер unknown

Опубликована: Янв. 31, 2024

ABSTRACT Type IV pili (T4Ps) are surface filaments widely distributed among bacteria and archaea. T4Ps involved in many cellular functions contribute to virulence some species of bacteria. Due the diversity T4Ps, different properties have been observed for homologous proteins that make up various organisms. In this review, we highlight essential components their functions, similarities related systems. We emphasize unique enteric pathogens within Enterobacteriaceae family, which includes pathogenic strains Escherichia coli Salmonella . These include bundle-forming pilus (BFP) enteropathogenic E. (EPEC), longus (Lng) colonization factor III (CFA/III) enterotoxigenic (ETEC), T4P enterica serovar Typhi, Colonization Factor Citrobacter (CFC) rodentium , Yersinia pseudotuberculosis a ubiquitous was characterized enterohemorrhagic (EHEC), R64 plasmid thin pilus. Finally, areas further study.

Язык: Английский

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The Dynamic Structures of the Type IV Pilus

Microbiology Spectrum, Год журнала: 2019, Номер 7(2)

Опубликована: Март 2, 2019

Type IV pilus (T4P)-like systems have been identified in almost every major phylum of prokaryotic life. They include the type IVa (T4aP), II secretion system (T2SS), IVb (T4bP), Tad/Flp pilus, Com and archaeal flagellum (archaellum). These are used for adhesion, natural competence, phage adsorption, folded-protein secretion, surface sensing, swimming motility, twitching motility. The T4aP allows all these functions except is therefore a good model understanding T4P-like systems. Recent structural analyses revolutionized our how machinery assembles functions. Here we review structure function T4aP.

Язык: Английский

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Structure and Assembly of the Enterohemorrhagic Escherichia coli Type 4 Pilus

Structure, Год журнала: 2019, Номер 27(7), С. 1082 - 1093.e5

Опубликована: Май 2, 2019

Язык: Английский

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