Lacinutrix algicola sp nov and Lacinutrix mariniflava sp nov., two novel marine alga-associated bacteria and emended description of the genus Lacinutrix

Abstract

Two heterotrophic, aerobic, yellow-pigmented, Gram-negative, non-gliding bacteria, designated AKS293(T) and AKS432(T) isolated from a red alga, were analysed using a polyphasic, taxonomic approach. 16S rRNA gene sequence analysis revealed that the novel strains were affiliated to the genus Lacinutrix, a member of the family Flavobacteriaceae, showing sequence similarities of 96.1-96.4 % with respect to the type strain of Lacinutrix copepodicola. The two novel isolates shared 99.5% 16S rRNA gene sequence similarity and 55.0 % DNA-DNA relatedness. They grew optimally at 17.5 degrees C and pH 6.5. The main cellular fatty acids of strain AKS293(T) were iso-C-(15: 0), iso-C-15: 0-OH and iso-C-16: 0 3-OH, while those of strain AKS432(T) were anteiso-C-15: 0, iso-C-15: 0, iso-C-15: 1 and iso-C-15:0 3-OH. In both cases, the major isoprenoid quinone was MK6. The DNA G + C contents were 34.7 and 37.0 mol% for strains AKS293(T) and AKS432(T), respectively. The phylogenetic evidence, phenotypic data and DNA-DNA hybridization results support the differentiation of strains AKS293(T) and AKS432(T) from each other and from their closest relative, L. copepodicola DJ3 T. Therefore, strains AKS293(T) and AKS432 T represent two novel species, for which the names Lacinutrix algicola sp. nov. and Lacinutrix mariniflava sp. nov. are proposed, respectively. The type strain of L. algicola sp. nov. is AKS293(T) (=KCCM 42313(T)=JjCM 13825(T)) and the type strain of L. mariniflava sp. nov. is AKS432(T) (=KCCIM 42306 T-jCM 13824 T). An emencled description of the genus Lacinutrix is also proposed.