Dissecting the molecular diversity and commonality of bovine and human treponemes identifies key survival and adhesion mechanisms

Autor: Jonathan M. Wastling, Alistair C. Darby, Stuart Ainsworth, Nicholas Evans, Gareth J. Staton, Stuart D. Armstrong, Neil Hall, Stuart D. Carter, Alan D Radford, Simon R. Clegg
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Bacterial Diseases
Cell Membranes
Pathogenesis
Pathology and Laboratory Medicine
Genome
Treponematoses
Medical Conditions
Medicine and Health Sciences
Biology (General)
Treponema Pallidum
Pathogen
Phylogeny
0303 health sciences
Genomics
Bacterial Pathogens
Infectious Diseases
Medical Microbiology
C432 Veterinary Genetics
Digital Dermatitis
Host adaptation
Pathogens
Cellular Structures and Organelles
Bacterial outer membrane
Research Article
Neglected Tropical Diseases
DNA
Bacterial

Virulence Factors
QH301-705.5
Urology
Immunology
Sexually Transmitted Diseases
Biology
Microbiology
Human Genomics
03 medical and health sciences
Virology
Genetics
Animals
Humans
Treponema
Secretion
Syphilis
Microbial Pathogens
Molecular Biology
Gene
030304 developmental biology
Treponemal Infections
Genitourinary Infections
030306 microbiology
QH
Biology and Life Sciences
Membrane Proteins
Cell Biology
RC581-607
Tropical Diseases
Outer Membrane Proteins
Bacterial adhesin
C430 Medical and Veterinary Genetics
Cattle
Parasitology
Immunologic diseases. Allergy
C520 Medical and Veterinary Microbiology
Zdroj: PLoS Pathogens, Vol 17, Iss 3, p e1009464 (2021)
PLoS Pathogens
ISSN: 1553-7374
Popis: Here, we report the first complete genomes of three cultivable treponeme species from bovine digital dermatitis (DD) skin lesions, two comparative human treponemes, considered indistinguishable from bovine DD species, and a bovine gastrointestinal (GI) treponeme isolate. Key genomic differences between bovine and human treponemes implicate microbial mechanisms that enhance knowledge of how DD, a severe disease of ruminants, has emerged into a prolific, worldwide disease. Bovine DD treponemes have additional oxidative stress genes compared to nearest human-isolated relatives, suggesting better oxidative stress tolerance, and potentially explaining how bovine strains can colonize skin surfaces. Comparison of both bovine DD and GI treponemes as well as bovine pathogenic and human non-pathogenic saprophyte Treponema phagedenis strains indicates genes encoding a five-enzyme biosynthetic pathway for production of 2,3-diacetamido-2,3-dideoxy-d-mannuronic acid, a rare di-N-acetylated mannuronic acid sugar, as important for pathogenesis. Bovine T. phagedenis strains further differed from human strains by having unique genetic clusters including components of a type IV secretion system and a phosphate utilisation system including phoU, a gene associated with osmotic stress survival. Proteomic analyses confirmed bovine derived T. phagedenis exhibits expression of PhoU but not the putative secretion system, whilst the novel mannuronic acid pathway was expressed in near entirety across the DD treponemes. Analysis of osmotic stress response in water identified a difference between bovine and human T. phagedenis with bovine strains exhibiting enhanced survival. This novel mechanism could enable a selective advantage, allowing environmental persistence and transmission of bovine T. phagedenis. Finally, we investigated putative outer membrane protein (OMP) ortholog families across the DD treponemes and identified several families as multi-specific adhesins capable of binding extra cellular matrix (ECM) components. One bovine pathogen specific adhesin ortholog family showed considerable serodiagnostic potential with the Treponema medium representative demonstrating considerable disease specificity (91.6%). This work has shed light on treponeme host adaptation and has identified candidate molecules for future diagnostics, vaccination and therapeutic intervention.
Author summary Bovine digital dermatitis (DD) is a severe infectious disease causing cattle lameness, which is now endemic in many countries across the world. This lameness results from inflamed lesions between the heel bulbs and is very painful resulting in poor animal welfare and substantially reduced production. There remains no single cure for DD and whilst topical antibiotic treatment enables some healing, lesions frequently reappear. Current evidence implicates bacteria known as Treponema in the pathogenesis of DD. Here we characterise the genomes of several bovine DD treponeme species as well as related bacteria from humans and the bovine gastrointestinal tract. Comparative analyses demonstrate that production of a novel mannuronic acid sugar is a key feature of bovine pathogens and several survival mechanisms were identified which likely enable the bovine pathogens to inhabit the skin surface and be transmitted within the farm environment. Studies investigating putative outer membrane proteins which are potential vaccine candidates identified that the majority have a role in host attachment, with one family of proteins exhibiting particular promise as serodiagnostic antigens. This increased understanding of the considered causal pathogens of bovine DD, together with the genomic and proteomic resources produced by this study should underpin future diagnostic, vaccination and therapeutics studies to combat this severe disease of ruminants.
Databáze: OpenAIRE