Aureimonas jatrophae sp. nov. and Aureimonas phyllosphaerae sp. nov., leaf-associated bacteria isolated from Jatropha curcas L

Abstract

Four orange-pigmented isolates, L7-456, L7-484T, L9-479 and L9-753T, originating from surface-sterilized leaf tissues of Jatropha curcas L. cultivars were characterized using a polyphasic taxonomic approach. Phylogenetic analyses based on 16S rRNA gene sequences indicated that all four isolates belong to the genus Aureimonas. In these analyses, strain L7-484T appeared to be most closely related to Aureimonas ureilytica 5715S-12T (95.7 % sequence identity). The 16S rRNA gene sequences of strains L7-456, L9-479 and L9-753T were found to be identical and also shared the highest similarity with A. ureilytica 5715S-12T (97.5 %). Both L7-484T and L9-753T contained Q-10 and Q-9 as predominant ubiquinones and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidyldimethylethanolamine, sulfoquinovosyldiacylglycerol and an aminophospholipid as the major polar lipids. C18: 1ω7c and C16: 0 were the major fatty acids. Similar to other species in the genus Aureimonas, hydroxylated fatty acids (e.g. C18: 1 2-OH) and cyclic fatty acids (C19: 0 cyclo ω8c) were also present. The DNA G+C contents of L7-484T and L9-753T were 66.1 and 69.4 mol%, respectively. Strains L7-484T and L9-753T exhibited less than 40 % DNA-DNA hybridization both between themselves and to A. ureilytica KACC 11607T. Our results support the proposal that strain L7-484Trepresents a novel species within the genus Aureimonas, for which the nameAureimonas jatrophae sp. nov. is proposed, and that strains L9-753T, L7-456 (= KACC 16229 = DSM 25023) and L9-479 (= KACC 16228 = DSM 25024) represent a second novel species within the genus, for which the nameAureimonas phyllosphaerae sp. nov. is proposed. The type strains ofAureimonas jatrophae sp. nov. and Aureimonas phyllosphaerae sp. nov. are respectively L7-484T (= KACC 16230T = DSM 25025T) and L9-753T (= KACC 16231T = DSM 25026T). © 2013 IUMS.