Formicincola oecophyllae gen. nov. sp. nov., a novel member of the family Acetobacteraceae isolated from the weaver ant Oecophylla smaragdina.

In this study, a novel bacterium designated F3b2 was isolated from the gut sample of weaver ant Oecophylla smaragdina and characterised. Strain F3b2 was a Gram-negative, aerobic, non-motile, ovoid-shaped bacterium and grows optimally at 28-30 °C. Its major respiratory quinone is ubiquinone 10 (Q-10) and the major fatty acids are C ω7c, C cyclo ω8c and C, representing 85% of the total fatty acids. The 16S rRNA gene sequence of strain F3b2 was highest in similarity to that of Oecophyllibacter saccharovorans DSM106907 and Swingsia samuieinsis NBRC 107927 at 94.35% and 91.96%, respectively. A 16S rRNA gene-based phylogenetic analysis and a core genes-based phylogenomic analysis placed strain F3b2 in a distinct lineage in the family Acetobacteraceae. The phylogenetic placement was supported by lower than species delineation threshold average nucleotide identity (ANI) (≤ 70.2%), in silico DNA-DNA hybridization (DDH) (≤ 39.5%) and average amino acid identity (AAI) (≤ 63.5%) values between strain F3b2 and closest neighbours. These overall genome relatedness indices also supported the assignment of strain F3b2 to a novel genus within Acetobacteraceae. The genome of strain F3b2 was 1.96 Mb with 60.4% G + C DNA content. Based on these results, strain F3b2 represented a novel taxon of Acetobacteraceae, for which we proposed the name Formicincola oecophyllae gen. nov. sp. nov., and strain F3b2 (= LMG 30590 = DSM 106908 = NBRC 113640 = KCTC 62951) as the type strain.