Komagataeibacter ossonobensis sp. nov., a novel bacterial cellulose producer isolated from an artisanal Mediterranean acetification.

Abstract

Bacterial strain CS8T, a novel bacterial cellulose producer, was isolated from a 'mother of vinegar' during an artisanal acetification process in Faro, Portugal and characterized. Strain CS8T stained Gram-negative and formed rod-shaped cells that grew optimally at 30 °C and at pH 5.5-6.5. Phylogenetic analyses based on the 16S rRNA gene placed strain CS8T within the genus Komagataeibacter in a distinct lineage, showing the highest sequence similarity to Komagataeibacter diospyri (99.86%), Komagataeibacter piraceti (99.80%), Komagataeibacter europaeus (99.80%), Komagataeibacter sucrofermentans (99.79%) and Komagataeibacter nataicola (99.72%). Genomic analysis revealed that overall genome relatedness index values of CS8ᵀ with K. europaeus LMG 18890ᵀ, Komagataeibacter swingsii LMG 22125ᵀ and K. diospyri MSKU 9T were 93.7% average nucleotide identity (ANI) and 53.3% digital DNA-DNA hybridization (dDDH), 91.7% ANI and 44.7% dDDH and 90.4 and 40.4%, respectively, which are below the species delineation thresholds. The genomic DNA G+C content of CS8ᵀ is 60.7 mol%. The draft genome sequence of strain CS8T comprises 4,020,094 bases with a 225-fold mapped genome coverage. The assembled genome consists of 131 large contigs with more than 500 bp and the genome encodes 4,229 putative coding sequences. Phylogenomic analysis based on 823 core genes placed strain CS8ᵀ in a distinct clade within the genus Komagataeibacter, clustering closely with Komagataeibacter europaeus LMG 18890ᵀ. Analysis of the CS8T genome revealed the presence of the terpene, hserlactone, triceptide and methanobactin biosynthetic gene clusters. The strain harbours a complete bcs gene operon and efficiently produces bacterial cellulose from glucose. The phylogenomic, phylogenetic, phenotypic and chemotaxonomic data showed that the strain CS8T (=UCCCB 286T=CECT 31419T) represents the type of a novel species, for which we propose the name Komagataeibacter ossonobensis sp. nov.