Gallibacterium faecale sp. nov., Isolated from Dairy Cow Feces

Area of Science:

• Microbiology
• Bacteriology
• Genomics

Background:

• The genus Gallibacterium comprises Gram-negative bacteria with implications in animal health.
• Isolation of novel strains is crucial for understanding microbial diversity and host-associated bacteria.

Purpose of the Study:

• To characterize a novel bacterial strain, AGMB14963^T, isolated from dairy cow feces.
• To determine the taxonomic placement of strain AGMB14963^T within the genus Gallibacterium.

Main Methods:

• Isolation and cultivation of bacterial strain AGMB14963^T from dairy cow feces.
• 16S rRNA gene sequencing for phylogenetic analysis.
• Whole-genome sequencing for genomic content, G+C percentage, and gene content analysis.
• Physiological and chemotaxonomic characterization, including biochemical tests and fatty acid analysis.

Main Results:

• Strain AGMB14963^T is a facultative anaerobic, Gram-negative, non-motile rod.
• Phylogenetic analysis showed highest similarity (95.8%) to Gallibacterium salpingitidis F150^T.
• Genomic analysis revealed a G+C content of 37.0% and a genome size of 2.58 Mb.
• Average nucleotide identity (82.3%) and digital DNA-DNA hybridization (24.9%) values supported novelty.
• Strain AGMB14963^T exhibited positive oxidase and catalase reactions, optimal growth at 37°C, pH 8, and 0.5% NaCl.
• Predominant fatty acids included C_14:0, C_16:0, and summed feature 3; major fermentation products were lactic and isobutyric acids.

Conclusions:

• Strain AGMB14963^T represents a novel species within the genus Gallibacterium based on genomic, physiological, and chemotaxonomic data.
• The proposed name for this new species is Gallibacterium faecale sp. nov., with AGMB14963^T as the type strain.