Pasteurellaceae bacteria from the oral cavity of Tasmanian devils (Sarcophilus Harrisii) show high minimum inhibitory concentration values towards aminoglycosides and clindamycin

Comparative Genome Analysis of Canine Frederiksenia canicola Isolates

Background/Objectives: The One Health approach is crucial for managing and controlling the spread of antimicrobial resistance. Frederiksenia canicola is a recently identified bacterial species that seems to be a component of the oral microbiota of dogs; however, its pathogenic nature is questionable. Methods: In this study, the antibacterial susceptibility of F. canicola isolates was determined using the disk diffusion and broth microdilution methods. Genome-wide comparative analyses were performed to identify the genetic factors driving virulence and antimicrobial drug resistance (e.g., virulence factors, antimicrobial resistance genes (ARGs) and prophage-related sequences). Results: Most of the F. canicola isolates lacked virulence-associated genes. F. canicola is likely resistant to clindamycin, lincomycin and neomycin, but susceptible to penicillin, erythromycin and enrofloxacin. Antimicrobial resistance genes were not found in the F. canicola genomes, but prophage-related sequences were identified, suggesting its potential in the transfer of genes associated with drug resistance between bacteria in the oral microbiome. Conclusions: F. canicola is presumably a commensal organism with low virulence potential, as evidenced by the absence of virulence-associated genes. As F. canicola can colonize a wide range of hosts, including humans, further investigation with a greater number of isolates is needed to better understand the role of F. canicola in disease development and the spread of drug resistance.

Detection of Frederiksenia sp. isolated from a cat with nephritis - Short communication

In this paper we report the phenotypic and partial genetic characterisation of a novel bacterium strain isolated from a cat with severe nephritis. Multilocus sequence analysis was performed on the 16S rRNA and three housekeeping (recN, rpoB, infB) gene sequences obtained by PCR. In accordance with the results of phenotypic tests, the phylogenetic analyses confirmed the relatedness of the new strain (6036) to the family Pasteurellaceae. On the phylogenetic trees, strain 6036 appeared in a separate branch, closest to that of the type species (Frederiksenia canicola) of the genus Frederiksenia. These two bacteria shared 95.14 and 76.88% identity in their partial 16S rRNA and recN gene sequences, respectively. The rpoB- and infB-based phylogenetic analyses indicated that strain 6036 is most closely related to Bibersteinia trehalosi (with 90.58% identity) and [Haemophilus] felis ATCC 49733 (89.50% identity), respectively. The predicted genome identity values, based on the recN gene sequences, suggested that strain 6036 can be classified into the genus Frederiksenia as a novel species. A PCR method, specific to strain 6036, was developed to allow its rapid and accurate identification and differentiation from F. canicola and other species of Pasteurellaceae. The minimal inhibitory concentrations of 18 antimicrobial agents for strain 6036 were also determined.

Ecology and Host Identity Outweigh Evolutionary History in Shaping the Bat Microbiome

This study is the first to provide a comprehensive survey of bacterial symbionts from multiple anatomical sites across a broad taxonomic range of Afrotropical bats, demonstrating significant associations between the bat microbiome and anatomical site, geographic locality, and host identity—but not evolutionary history. This study provides a framework for future systems biology approaches to examine host-symbiont relationships across broad taxonomic scales, emphasizing the need to elucidate the interplay between host ecology and evolutionary history in shaping the microbiome of different anatomical sites.

Recent studies of mammalian microbiomes have identified strong phylogenetic effects on bacterial community composition. Bats (Mammalia: Chiroptera) are among the most speciose mammals on the planet and the only mammal capable of true flight. We examined 1,236 16S rRNA amplicon libraries of the gut, oral, and skin microbiota from 497 Afrotropical bats (representing 9 families, 20 genera, and 31 species) to assess the extent to which host ecology and phylogeny predict microbial community similarity in bats. In contrast to recent studies of host-microbe associations in other mammals, we found no correlation between chiropteran phylogeny and bacterial community dissimilarity across the three anatomical sites sampled. For all anatomical sites, we found host species identity and geographic locality to be strong predictors of microbial community composition and observed a positive correlation between elevation and bacterial richness. Last, we identified significantly different bacterial associations within the gut microbiota of insectivorous and frugivorous bats. We conclude that the gut, oral, and skin microbiota of bats are shaped predominantly by ecological factors and do not exhibit the same degree of phylosymbiosis observed in other mammals.

IMPORTANCE This study is the first to provide a comprehensive survey of bacterial symbionts from multiple anatomical sites across a broad taxonomic range of Afrotropical bats, demonstrating significant associations between the bat microbiome and anatomical site, geographic locality, and host identity—but not evolutionary history. This study provides a framework for future systems biology approaches to examine host-symbiont relationships across broad taxonomic scales, emphasizing the need to elucidate the interplay between host ecology and evolutionary history in shaping the microbiome of different anatomical sites.

What's the risk? Identifying potential human pathogens within grey-headed flying foxes faeces

Pteropus poliocephalus (grey-headed flying foxes) are recognised vectors for a range of potentially fatal human pathogens. However, to date research has primarily focused on viral disease carriage, overlooking bacterial pathogens, which also represent a significant human disease risk. The current study applied 16S rRNA amplicon sequencing, community analysis and a multi-tiered database OTU picking approach to identify faecal-derived zoonotic bacteria within two colonies of P. poliocephalus from Victoria, Australia. Our data show that sequences associated with Enterobacteriaceae (62.8% ± 24.7%), Pasteurellaceae (19.9% ± 25.7%) and Moraxellaceae (9.4% ± 11.8%) dominate flying fox faeces. Further colony specific differences in bacterial faecal colonisation patterns were also identified. In total, 34 potential pathogens, representing 15 genera, were identified. However, species level definition was only possible for Clostridium perfringens, which likely represents a low infectious risk due to the low proportion observed within the faeces and high infectious dose required for transmission. In contrast, sequences associated with other pathogenic species clusters such as Haemophilus haemolyticus-H. influenzae and Salmonella bongori-S. enterica, were present at high proportions in the faeces, and due to their relatively low infectious doses and modes of transmissions, represent a greater potential human disease risk. These analyses of the microbial community composition of Pteropus poliocephalus have significantly advanced our understanding of the potential bacterial disease risk associated with flying foxes and should direct future epidemiological and quantitative microbial risk assessments to further define the health risks presented by these animals.