Leucobacter zeae sp. nov., isolated from the rhizosphere of maize (Zea mays L.)

Abstract

A novel yellow-pigmented, aerobic, rod-shaped, non-motile bacterium, designated strain CC-MF41T, was isolated from rhizosphere soil of maize (Zea mays) collected in Wufeng District, Taichung, Taiwan. Strain CC-MF41T exhibited 16S rRNA gene sequence similarity of 97.5, 97.3, 97.2 and 97.1 % to Leucobacter chironomi MM2LBT (and ‘Leucobacter kyeonggiensis’ F3-P9 and ‘L. humi’ Re-6, the names of which have not been validly published), Leucobacter tardus K70/01T, L. komagatae IFO 15245T and ‘Leucobacter margaritiformis’ A23. However, CC-MF41T and ‘L. margaritiformis’ A23 formed a loosely bound phylogenetic lineage (with a low bootstrap value) associated with species of the genus Leucobacter. In DNA–DNA reassociation experiments, the relatedness of strain CC-MF41T to L. chironomi DSM 19883T was 57.1 % (reciprocal value 29.1 %). The DNA G+C content of strain CC-MF41T was 72.1 mol% and the cell-wall peptidoglycan contained 2,4-diaminobutyric acid, alanine, glycine, glutamic acid and threonine. The major menaquinone was MK-11 and the predominant fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The polar lipid profile of strain CC-MF41T contained major amounts of diphosphatidylglycerol followed by an unidentified glycolipid, phosphatidylglycerol and an unknown phospholipid. Based on its phylogenetic, phenotypic and chemotaxonomic distinctiveness, strain CC-MF41T represents a novel species of Leucobacter, for which the name Leucobacter zeae sp. nov. is proposed. The type strain is CC-MF41T ( = BCRC 80515T = LMG 27265T).