Pangenomic and biochemical analyses of Helcococcus ovis reveal widespread tetracycline resistance and a novel bacterial species, Helcococcus bovis

Bibliographic Details
Title: Pangenomic and biochemical analyses of Helcococcus ovis reveal widespread tetracycline resistance and a novel bacterial species, Helcococcus bovis
Authors: Federico Cunha, Yuting Zhai, Segundo Casaro, Kristi L. Jones, Modesto Hernandez, Rafael S. Bisinotto, Subhashinie Kariyawasam, Mary B. Brown, Ashley Phillips, Kwangcheol C. Jeong, Klibs N. Galvão
Source: Frontiers in Microbiology, Vol 15 (2024)
Publisher Information: Frontiers Media S.A., 2024.
Publication Year: 2024
Collection: LCC:Microbiology
Subject Terms: whole genome sequencing (WGS), Helcococcus, novel species, tetracycline resistance, pangenome analysis, bovine, Microbiology, QR1-502
More Details: Helcococcus ovis (H. ovis) is an opportunistic bacterial pathogen of a wide range of animal hosts including domestic ruminants, swine, avians, and humans. In this study, we sequenced the genomes of 35 Helcococcus sp. clinical isolates from the uterus of dairy cows and explored their antimicrobial resistance and biochemical phenotypes in vitro. Phylogenetic and average nucleotide identity analyses classified four Helcococcus isolates within a cryptic clade representing an undescribed species, for which we propose the name Helcococcus bovis sp. nov. By establishing this new species clade, we also resolve the longstanding question of the classification of the Tongji strain responsible for a confirmed human conjunctival infection. This strain did not neatly fit into H. ovis and is instead a member of H. bovis. We applied whole genome comparative analyses to explore the pangenome, resistome, virulome, and taxonomic diversity of the remaining 31 H. ovis isolates. An overwhelming 97% of H. ovis strains (30 out of 31) harbor mobile tetracycline resistance genes and displayed significantly increased minimum inhibitory concentrations of tetracyclines in vitro. The high prevalence of mobile tetracycline resistance genes makes H. ovis a significant antimicrobial resistance gene reservoir in our food chain. Finally, the phylogenetic distribution of co-occurring high-virulence determinant genes of H. ovis across unlinked and distant loci highlights an instance of convergent gene loss in the species. In summary, this study showed that mobile genetic element-mediated tetracycline resistance is widespread in H. ovis, and that there is evidence of co-occurring virulence factors across clades suggesting convergent gene loss in the species. Finally, we introduced a novel Helcococcus species closely related to H. ovis, called H. bovis sp. nov., which has been reported to cause infection in humans.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1664-302X
Relation: https://www.frontiersin.org/articles/10.3389/fmicb.2024.1456569/full; https://doaj.org/toc/1664-302X
DOI: 10.3389/fmicb.2024.1456569
Access URL: https://doaj.org/article/c39adf09157c404e9b02a19a0591a834
Accession Number: edsdoj.39adf09157c404e9b02a19a0591a834
Database: Directory of Open Access Journals
More Details
ISSN:1664302X
DOI:10.3389/fmicb.2024.1456569
Published in:Frontiers in Microbiology
Language:English