A Gram-stain negative, aerobic, non-motile bacterial strain, 23D10-4-9T, was isolated from symptomatic canker bark tissue of Populus × euramericana. The isolate grew between 4 and 35 °C, with optimal growth occurring at 25 °C. The species was positive for catalase and negative for oxidase activity. Nitrate was not reduced to nitrite. It showed activities toward β-galactosidase and β-glucosidase. Citrate was not utilized. Acid was produced from d-glucose. The major fatty acids were iso-C15 : 0, C16 : 1ω7c and iso-C17 : 0 3-OH. The main polar lipid profiles of the novel isolate included phosphatidylethanolamine, phospholipids and seven unknown lipids. The predominant menaquinone of the novel isolate was MK-7. The DNA G+C content was 40.6 mol%. 16S rRNA gene data revealed that the novel isolate shares the greatest sequence similarity with Sphingobacterium populi 7Y-4T (96.1 %). Based on phenotypic and genotypic characteristics, the isolate represents a novel species within the genus Sphingobacterium, for which the name Sphingobacteriumcorticis sp. nov. is proposed. The type strain is 23D10-4-9T (=CFCC 12640T=KCTC 42248T).
Keywords: Populus × euramericana; Sphingobacterium corticis sp. nov.; bark.