The great divide: rhamnolipids mediate separation betweenP. aeruginosaandS. aureus DOI Creative Commons
Jean-Louis Bru, Summer J. Kasallis,

Rendell Chang

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: June 23, 2023

Abstract The coexistence of multiple bacterial species during infection can have significant impacts on pathogenesis. Pseudomonas aeruginosa and Staphylococcus aureus are opportunistic pathogens that co-infect hosts cause serious illness. factors dictate whether one will outcompete the other or two coexist not fully understood. We investigated role surfactants in interactions between these a surface enables P. to swarm. found swarms repelled by colonies clinical S. isolates, creating physical separation strains. This effect was abolished mutants were defective production phenol-soluble modulins (PSMs), which form amyloid fibrils around wild-type colonies. mechanism establishes using Imaging Reflected Illuminated Structures (IRIS) method, tracks flow rhamnolipid surfactant layer produced . PSMs deflected flow, turn, altered direction swarms. These findings show rhamnolipids mediate , distinct microenvironments. Additionally, we Bacillus subtilis abiotic hydrophobic molecules through deflection. Our results suggest could major bacteria-bacteria bacteria-host relationships. In addition, our uncover responsible for swarm development does rely sensing but instead is guided largely its boundaries.

Language: Английский

The role of Staphylococcus aureus quorum sensing in cutaneous and systemic infections DOI Creative Commons
Yuriko Yamazaki, Tomoka Ito, Masakazu Tamai

et al.

Inflammation and Regeneration, Journal Year: 2024, Volume and Issue: 44(1)

Published: March 1, 2024

Abstract Background Staphylococcus aureus is a leading cause of human bacterial infections worldwide. It the most common causative agent skin and soft tissue infections, can also various other including pneumonia, osteomyelitis, as well life-threatening such sepsis infective endocarditis. The pathogen asymptomatically colonize skin, nasal cavity, intestine. S. colonizes approximately 20–30% nostrils, being an opportunistic for subsequent infection. Its strong ability to silently spread via contact makes it difficult eradicate S . A major concern with its capacity develop antibiotic resistance adapt diverse environmental conditions. variability in accessory gene regulator (Agr) region genome contributes spectrum phenotypes within population, enhancing likelihood survival different environments. Agr functions central quorum sensing (QS) system , allowing bacteria adjust expression response population density. Depending on expression, secretes toxins, contributing virulence infectious diseases. Paradoxically, expressing may be disadvantageous certain situations, hospitals, causing generate mutants responsible healthcare settings. Main body This review aims demonstrate molecular mechanisms governing ranging from harmless colonizer organism capable infecting organs. Emphasis will placed QS role orchestrating behavior across contexts. Short conclusion pathophysiology infection substantially influenced by phenotypic changes resulting factors beyond Agr. Future studies are expected give comprehensive understanding overall profile

Language: Английский

Citations

25
Hierarchical assembly of intrinsically disordered short peptides DOI Creative Commons
Jiaqi Guo, Shane T. Rich-New, Chen Liu

et al.

Chem, Journal Year: 2023, Volume and Issue: 9(9), P. 2530 - 2546

Published: May 16, 2023

Language: Английский

Citations

28
The role of filamentous matrix molecules in shaping the architecture and emergent properties of bacterial biofilms DOI Creative Commons
Jan Böhning, Abul K. Tarafder, Tanmay A. M. Bharat

et al.

Biochemical Journal, Journal Year: 2024, Volume and Issue: 481(4), P. 245 - 263

Published: Feb. 15, 2024

Numerous bacteria naturally occur within spatially organised, multicellular communities called biofilms. Moreover, most bacterial infections proceed with biofilm formation, posing major challenges to human health. Within biofilms, cells are embedded in a primarily self-produced extracellular matrix, which is defining feature of all The matrix complex, viscous mixture composed polymeric substances such as polysaccharides, filamentous protein fibres, and DNA. structured arrangement the bestows beneficial emergent properties that not displayed by planktonic cells, conferring protection against physical chemical stresses, including antibiotic treatment. However, lack multi-scale information at molecular level has prevented better understanding this its properties. Here, we review recent progress on characterisation components their three-dimensional spatial organisation

Language: Английский

Citations

14
Functional Amyloids: Where Supramolecular Amyloid Assembly Controls Biological Activity or Generates New Functionality DOI Open Access

Jessica A. Buchanan,

Nikhil R. Varghese,

Caitlin Johnston

et al.

Journal of Molecular Biology, Journal Year: 2023, Volume and Issue: 435(11), P. 167919 - 167919

Published: June 1, 2023

Language: Английский

Citations

23
The Cryo-EM structures of two amphibian antimicrobial cross-β amyloid fibrils DOI Creative Commons
Robert Bücker, Carolin Seuring,

Cornelia Cazey

et al.

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: July 27, 2022

Abstract The amyloid-antimicrobial link hypothesis is based on antimicrobial properties found in human amyloids involved neurodegenerative and systemic diseases, along with amyloidal structural peptides (AMPs). Supporting this hypothesis, we here determined the fibril structure of two AMPs from amphibians, uperin 3.5 aurein 3.3, by cryogenic electron microscopy (cryo-EM), revealing amyloid cross-β fibrils mated β-sheets at atomic resolution. Uperin formed a 3-blade symmetrical propeller nine per layer including tight β-sheet interfaces. This cryo-EM complements cross-α conformation previously crystallography, substantiating secondary switch mechanism 3.5. 3.3 arrangement consisted six layer, all showing kinked allowing rounded compactness fibril. are similar to LARKS (Low-complexity, Amyloid-like, Reversible, Kinked Segments) functional amyloids.

Language: Английский

Citations

24
Long‐Range Proton Channels Constructed via Hierarchical Peptide Self‐Assembly DOI Creative Commons

Semion Censor,

Juana Robledo Martin,

Ohad Silberbush

et al.

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 12, 2024

Abstract The quest to understand and mimic proton translocation mechanisms in natural channels has driven the development of peptide‐based artificial facilitating efficient transport across nanometric membranes. It is demonstrated here that hierarchical peptide self‐assembly can form micrometers‐long nanochannels. fourfold symmetrical design leverages intermolecular aromatic interactions align self‐assembled cyclic nanotubes, creating hydrophilic nanochannels between them. Titratable amino acid sidechains are positioned adjacent each other within channels, enabling formation hydrogen‐bonded chains upon hydration, transport. Moreover, these enriched with protons water molecules by interacting immobile counter ions introduced into increasing flow density rate. This system maintains transfer rates closely resembling those protein over micrometer distances. functional behavior inherently recyclable biocompatible systems opens door for their exploitation diverse applications energy storage conversion, biomedicine, bioelectronics.

Language: Английский

Citations

4
Staphylococcus aureus delta toxin modulates both extracellular membrane vesicle biogenesis and amyloid formation DOI Creative Commons
X. Wang, Divakara S. S. M. Uppu, Seth W. Dickey

et al.

mBio, Journal Year: 2023, Volume and Issue: 14(5)

Published: Oct. 5, 2023

ABSTRACT Staphylococcus aureus secretes phenol-soluble modulins (PSMs), a family of small, amphipathic, secreted peptides with multiple biologic activities. Community-acquired S. strains produce high levels PSMs in planktonic cultures, and PSM alpha have been shown to augment the release extracellular membrane vesicles (MVs). We observed that amyloids, aggregates proteins characterized by fibrillar morphology stained specific dyes, co-purified MVs harvested from cell-free culture supernatants community-acquired strains. δ-toxin was major component amyloid fibrils strain LAC MVs, promoted production dose-dependent manner. To determine whether were generated under vivo conditions, we inoculated mice cultures. Bacterial isolated purified lavage fluids recovered infected animals. Although most abundant fluids, could not be detected these samples. Our findings expand our understanding fibril formation reveal important roles MV biogenesis, demonstrate are staphylococcal infection model. IMPORTANCE Extracellular (MVs) produced cultures encapsulate diverse cargo bacterial proteins, nucleic acids, glycopolymers protected destruction external factors. δ-toxin, member phenol soluble modulin family, critical for biogenesis. Amyloid virulent, strains, dependent on expression gene ( hld ). Mass spectrometry data confirmed comprised δ-toxin. localized murine model, setting. provide insights into factors involved biogenesis formation.

Language: Английский

Citations

10
Staphylococcus aureus functional amyloids catalyze degradation of β-lactam antibiotics DOI Creative Commons
Elad Arad, Kasper B. Pedersen,

Orit Malka

et al.

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Dec. 11, 2023

Abstract Antibiotic resistance of bacteria is considered one the most alarming developments in modern medicine. While varied pathways for acquiring antibiotic have been identified, there still are open questions concerning mechanisms underlying resistance. Here, we show that alpha phenol-soluble modulins (PSMαs), functional bacterial amyloids secreted by Staphylococcus aureus , catalyze hydrolysis β-lactams, a prominent class compounds. Specifically, PSMα2 and, particularly, PSMα3 amide-like bond four membered β-lactam ring nitrocefin, an surrogate. Examination catalytic activities several variants allowed mapping active sites on amyloid fibrils’ surface, specifically underscoring key roles cross-α fibril organization, and combined electrostatic nucleophilic functions lysine arrays. Molecular dynamics simulations further illuminate structural features association upon surface. Complementary experimental data underscore generality amyloid-mediated phenomenon, demonstrating clinically employed β-lactams fibrils, illustrating degradation actual S. biofilms live environments. Overall, this study unveils as agents inducing antibiotics, possible associated with biofilms.

Language: Английский

Citations

10
Structural and Functional Versatility of the Amyloidogenic Antimicrobial Peptide Citropin 1.3 DOI Creative Commons
Fabio Strati, Mariana P. Cali,

Yehudi Bloch

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 31, 2025

Abstract Citropin 1.3 is an antimicrobial peptide produced by the amphibian Litoria citropa (Southern bell frog), which self-aggregates into distinct fibrillar structures, however, function of fibrils remains unclear and largely unexplored. In this study, structural functional properties citropin were investigated using cryogenic electron microscopy fluorescence in presence membrane cell models, with X-ray crystallography. Canonical amyloids, multilayered nanotubes, a novel mixed fibril observed. Experiments negatively charged giant unilamellar vesicles revealed that facilitates fusion while simultaneously undergoing phase separation phospholipids. mammalian cells, permeabilizes membranes, leading to death, over time, colocalizes genetic material. Overall, work provides new insights dynamics amyloidogenic its interactions different systems.

Language: Английский

Citations

0
The Roles of Functional Bacterial Amyloids in Neurological Physiology and Pathophysiology: Pros and Cons for Neurodegeneration DOI

Hossein Halimi,

Babak Ahmadi, Nastaran Asri

et al.

Microbial Pathogenesis, Journal Year: 2025, Volume and Issue: unknown, P. 107363 - 107363

Published: Feb. 1, 2025

Language: Английский

Citations

0