Komagataeibacter diospyri sp. nov., a novel species of thermotolerant bacterial nanocellulose-producing bacterium

Abstract

Thermotolerant bacterial nanocellulose-producing strains, designated MSKU 9^T and MSKU 15, were isolated from persimmon and sapodilla fruits, respectively. These strains were aerobic, Gram-stain-negative, had rod-shaped cells, were non-motile and formed white-cream colonies. Phylogeny based on the 16S rRNA gene sequences revealed that MSKU 9^T and MSKU 15 represented members of the genus <i>Komagataeibacter</i> and formed a monophyletic branch with <i>K. swingsii</i> JCM 17123^T and <i>K. europaeus</i> DSM 6160^T. The genomic analysis revealed that overall genomic relatedness index values of MSKU 9^T with <i>K. swingsii</i> JCM 17123^T and <i>K. europaeus</i> DSM 6160^T were ~90 % average nucleotide identity (ANI) and ≤58.2 % digital DNA-DNA hybridization (dDDH), respectively. MSKU 9^T and MSKU 15 can be differentiated from the closely related <i>K. swingsii</i> JCM 17123^T by their growth on 30 % d-glucose and ability to utilize and to form acid from raffinose and sucrose as carbon sources, and from <i>K. europaeus</i> DSM 6160^T by their ability to grow without acetic acid. The genomic DNA G+C contents of MSKU 9^T and MSKU 15 were 60.4 and 60.2 mol%, respectively. The major fatty acids of MSKU 9^T and MSKU 15 were summed feature 8 (C_{18 : 1} <i> </i>ω7c and/or C_{18 : 1}ω6c). The respiratory quinone was determined to be Q10. On the basis of the results of the polyphasic taxonomic analysis, MSKU 9^T (=TBRC 9844^T=NBRC 113802^T) represents a novel species of the genus <i>Komagataeibacter</i>, for which the name <i>Komagataeibacter</i> <i>diospyri</i> sp. nov. is proposed.