Lysobacter capsici sp. nov., with antimicrobial activity, isolated from the rhizosphere of pepper, and emended description of the genus Lysobacter

Abstract

The taxonomic position of a novel bacterial strain, YC5194(T), with antimicrobial activity, isolated from the rhizosphere of pepper in Jinju, South Korea, was studied using a polyphasic approach. Cells of the strain were Gram-negative, rod-shaped, facultative anaerobes. It grew at a temperature of 15-37 degrees C (optimum 28 degrees C). Growth of the strain occurred between pH 5.5 and 8.5, with an optimum of pH 7.0-7.5. The strain inhibited mycelial growth of Pythium ultimum, Colletotrichum gloeosporioides, Fusarium oxysporum, Botrytis cinerea, Rhizoctonia solani and Botryosphaeria dothidea and growth of Bacillus subtilis. The G+C content of the total DNA was 65.4 mol%. The 16S rRNA gene sequence of the strain was most closely related to species of the genus Lysobacter (<94.0 to >99.0 % sequence similarity). Chemotaxonomic data (major quinone, Q-8; major polar lipids, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidyl-N-methylethanolamine; major fatty acids, iso-C(15 : 0), summed feature 3, C(16 : 0), iso-C(17 : 1)omega9c and C(18 : 1)omega7c) supported the affiliation of strain YC5194(T) to the genus Lysobacter. Phylogenetic analysis based on 16S rRNA gene sequences, DNA-DNA hybridization data and biochemical and physiological characteristics strongly supported the genotypic and phenotypic differentiation of strain YC5194(T) from species of Lysobacter with validly published names. Strain YC5194(T) therefore represents a novel species, for which the name Lysobacter capsici sp. nov. is proposed. The type strain is YC5194(T) (=KCTC 22007(T) =DSM 19286(T)).