Lelliottia steviae sp. nov. isolated from Stevia rebaudiana Bertoni.

Abstract

A Gram-negative, aerobic, chemoheterotrophic, rod-shaped, and motile bacterium, designated as LST-1T, was isolated from wild Stevia rebaudiana Bertoni and subjected to a polyphasic taxonomic analysis. The LST-1 strain grew optimally at 37°C and pH 6.0-7.0 in the presence of 0.5% (w/v) NaCl. Phylogenetic analysis based on the 16S rDNA sequence indicated that LST-1 is closely related to Lelliottia jeotgali PFL01T (99.85%), Lelliottia nimipressuralis LMG10245T (98.82%), and Lelliottia amnigena LMG2784T (98.54%). Multi-locus sequence typing of concatenated partial atpD, infB, gyrB, and rpoB genes was performed to improve the resolution, and clear distinctions between the closest related type strains were observed. The results of average nucleotide identify analyses and DNA-DNA hybridization with four species (16S rDNA similarity > 98.65%) were less than 90 and 40%, respectively, verifying the distinct characteristics from other species of Lelliottia. The cellular fatty acid profile of the strain consisted of C16:0, Summed Feature3, and Summed Feature8 (possibly 16:1 w6c/16:1 w7c and 18:1 w6c) as major components. The major polar lipids included phosphatidylethanolamine, phosphatidylglycerol, an aminophospholipid, three non-characteristic phospholipids, and a non-characteristic lipid. The genome of LST-1T was 4,611,055bp in size, with a G + C content of 55.02%. The unique combination of several phenotypic, chemotaxonomic, and genomic characteristics proved that strain LST-1T belongs to a novel species, for which the name Lelliottia steviae sp. nov. is proposed. The type strain is LST-1T (= CGMCC 1.19175T = JCM 34938T).Repositories: The genbank accession numbers for the 16S rRNA gene and genome sequences of strain LST-1T are MZ497264 and CP063663, respectively.