Hoeflea suaedae sp. nov., an endophytic bacterium isolated from the root of the halophyte Suaeda maritima

Abstract

A Gram-negative, aerobic, short rod-shaped bacterium, designated strain YC6898T, was isolated from the surface-sterilized root of a halophyte (Suaeda maritima) inhabiting tidal flat of Namhae Island, Korea. Strain YC6898Tgrew optimally at 30–37 °C and pH 6.5–7.5. The strain inhibited mycelial growth ofPythium ultimumandPhytophthora capsici. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain YC6898Tbelongs to the genusHoefleain the familyPhyllobacteriaceae. Its closest relatives wereHoeflea alexandriiAM1V30T(96.7 % 16S rRNA gene sequence similarity),Hoeflea anabaenaeWH2KT(95.7 %),Hoeflea phototrophicaDFL-43T(95.5 %) andHoeflea marinaLMG 128T(94.8 %). Strain YC6898Tcontained Q-10 as the major ubiquinone. The major fatty acids of strain YC6898Twere C18 : 1ω7c(61.1 %), C16 : 0(11.9 %), 11-methyl C18 : 1ω7c(9.6 %) and C19 : 0cyclo ω8c(8.0 %). The polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, unknown lipids and an unknown glycolipid. The total genomic DNA G+C content was 53.7 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic analysis, strain YC6898Trepresents a novel species of the genusHoeflea, for which the nameHoeflea suaedaesp. nov. is proposed. The type strain is YC6898T( = KACC 14911T = NBRC 107700T).