Pontibacter silvestris sp. nov., isolated from the soil of a Populus euphratica forest and emended description of the genus Pontibacter.

Strain XAAS-R86, a Gram-stain-negative, short rod-shaped, non-motile, aerobic bacterium, was isolated from a Populus euphratica forest near the city of Hotan, Xinjiang, PR China. The cells were found to be positive for catalase and oxidase activities. Growth occurred optimally at 28-30 °C, pH 7.0-7.5 and in the presence of 0.5-2.0 % NaCl (w/v). The results of phylogenetic analysis of the 16S rRNA gene indicated that XAAS-R86 represents a member of the genus Pontibacter within the family Hymenobacteraceae. Pontibacter akesuensis CCTCC AB 206086 is the most closely related species with a validly published name, based on 16S rRNA gene sequence identity (95.7 %). The DNA G+C content of the strain is 43.9 mol%. The main respiratory quinone is MK-7 and the major cellular fatty acids are summed feature 4 (iso-C17 : 1I and/or anteiso-C17 : 1B) and iso-C15 : 0 and its major polar lipids are phosphatidylethanolamine and two unidentified lipids. On the basis of the results of tests performed using a polyphasic approach, XAAS-R86 represents a novel species of the genus Pontibacter, for which the name Pontibactersilvestris sp. nov. is proposed, with the type strain XAAS-R86 (=CCTCC AB 2017165=KCTC 62047).