Reclassification of Moraxella boevrei, M. osloensis and M. atlantae, into the genus Faucicola, and proposal of a new genus within the family Moraxellaceae, Lwoffella lincolnii gen. nov., comb. nov., to accommodate the divergent species Moraxella lincolnii.

Abstract

The genus Moraxella (Moraxellaceae, Pseudomonadales) comprises a diverse group of bacteria inhabiting human and animal mucosa, as well as environmental niches such as water, soil and food. While some species are clinically significant pathogens, others play ecological or biotechnological roles. Despite previous taxonomic revisions, Moraxella remains polyphyletic, necessitating a refined classification. In this study, we conducted comprehensive taxogenomic analyses integrating core protein phylogeny, average amino acid identity and the percentage of conserved proteins, along with 16S rRNA similarities and inferred phylogeny. Our results revealed three distinct phylogenetic clusters within Moraxella. The core group, comprising Moraxella lacunata NBRC 102154^T and closely related species, exhibited strong genomic cohesion. A second cluster, consisting of Moraxella boevrei DSM 14165^T, Moraxella osloensis CCUG 350^T and Moraxella atlantae NBRC 14588^T, showed greater genetic affinity to Faucicola mancuniensis GVCNT2^T, supporting their reassignment to the genus Faucicola. The third group, represented by Moraxella lincolnii CCUG 9405^T, was phylogenetically distinct, occupying a basal position relative to Psychrobacter, indicating the need for its classification within a novel genus within the family Moraxellaceae, for which we propose the name Lwoffella lincolnii gen. nov., comb. nov. Phenotypic data compiled from the original published descriptions of the respective species, including fatty acid composition and enzymatic profiles, further corroborated these genomic findings. This study refines Moraxella taxonomy by clarifying genus boundaries and evolutionary relationships, with implications for ecology and clinical microbiology.