Abstract
Four Gram-negative, facultative anaerobic, oxidase-negative and catalase-positive strains were isolated from lettuce sample collected from test beds at the National Institute of Agricultural Sciences in Wanju, South Korea. The whole genome sequences of the strains ranged from 4,624,629 to 4,849,846 bp in size, with DNA G + C contents of 54.32 to 54.56 mol%. Phylogenetic analyses based on 16S rRNA gene and four housekeeping (atpD, gyrB, infB, and rpoB) gene sequences showed that the four strains clustered closely together with Scandinavium type strains within the Enterobacteriaceae family. Moreover, the average nucleotide identity and digital DNA-DNA hybridization value of the proposed type strain (V105_6(T)) with the closely related Scandinavium type strains were in the range of 85.71-86.16% and 30.2-31.2%, respectively, which were all below the species delineation threshold values. The major cellular fatty acid of V105_6(T) was C(16:0). Growth was observed at 7, 10 and 35 °C, and in the presence of 7% NaCl concentration. Based on phenotypic and genotypic results, strain V105_6(T) represents a novel species of the genus Scandinavium, for which the name Scandinavium lactucae sp. nov. is proposed. The type strain is V105_6(T) (= LMG 33389(T) = DSM 117134(T)).