Arboribacterium acericorticis gen. nov., sp. nov., an under-represented oligotrophic bacterium of the phylum Abditibacteriota isolated from the bark of Acer palmatum

Only a small fraction of environmental micro-organisms has been isolated and cultivated, and deepening our understanding of under-represented taxa is important for unveiling unknown microbial ecosystems and accumulating bioresources. To date, only one strain of the phylum <i>Abditibacteriota</i> has been isolated and remains poorly characterized. We isolated strain IAD-21^T, a member of the phylum <i>Abditibacteriota</i>, from the bark of <i>Acer palmatum</i>, and its characteristics are described in this report. Strain IAD-21^T is a Gram-negative, oligotrophic, slow-growing, aerobic heterotrophic bacterium, and its cells are tetrad or sarcina cocci. The growth temperature and pH range from 15 to 37 °C and 6.0 to 7.4, respectively, and the strain forms pink colonies on agar medium. The 16S rRNA gene sequence similarity between this strain and <i>Abditibacterium utsteinense</i> strain LMG 29911^T was 90.83%, and the average amino acid identity and percentage of conserved proteins values were 63.93% and 48.80%, respectively. Phylogenetic analysis based on the 16S rRNA gene and genome sequences revealed that strains IAD-21^T and LMG 29911^T were placed in separate clusters. The genome size of strain IAD-21^T was 7.4 Mb, and it contained a 102 kb plasmid. The G+C content of the genomic DNA was 55.05 mol%. The genome sequence of strain IAD-21^T contains genes encoding various carbohydrate-active enzymes, suggesting that this strain is involved in the degradation of plant cell wall components. Based on the phylogenetic and physiological analyses, we propose the name <i>Arboribacterium acericorticis</i> gen. nov., sp. nov. (type strain IAD-21^T=JCM 32665^T=DSM 108248^T), which belongs to the family <i>Abditibacteriaceae</i>.