Spirosoma terrae sp. nov., Isolated from Soil from Jeju Island, Korea

Abstract

The taxonomic position of bacterial strain, designated 15J9-4T, recovered from a beach soil sample on Jeju Island, South Korea, was established using a polyphasic approach. Strain 15J9-4T was assigned to phylum Bacteroidetes within the family Cytophagaceae based on 16S rRNA gene similarities. The closest phylogenetic relatives with validly published names were Spirosoma panaciterrae Gsoil 1519T (94.2% similarity) and Spirosoma luteolum 16F6ET (94.1%). Cells were rod-shaped, Gram-stain-negative, and non-motile. The isolate grew on NA, R2A, TSA, and LB agar. The temperature limits for growth were 10 and 30°C with an optimum at 25°C and the pH range was 7-8. Menaquinone MK-7 was the predominant respiratory quinone. The major cellular fatty acids comprised summed feature 3 (C16:1 ω6c/C16:1 ω7c, 30.2%), C16:1 ω5c (22.2%), iso C15:0 (12.9%), and C16:0 (8.8%). Phosphatidylethanolamine was identified as the major polar lipid. The G+C content of the genomic DNA was 48.4mol%. The results obtained from the polyphasic analyses allowed for the genotypic and phenotypic differentiation of strain 15J9-4T from recognized Spirosoma species. Therefore, the isolate is considered to represent a novel species in the genus Spirosoma, for which the name Spirosoma terrae sp. nov. is proposed. The type strain is 15J9-4T (= KCTC 52035T = JCM 31994T).