Halomonas andesensis sp. nov., a moderate halophile isolated from the saline lake Laguna Colorada in Bolivia

Abstract

A moderately halophilic, motile, Gram-negative, rod-shaped bacterium, strain LC6(T), was isolated from a water sample of lake Laguna Colorada in the Bolivian Andes. The major cellular fatty acids were C(18 : 1)omega7c, iso-C(16 : 1)omega7c 2-OH, C(16 : 0) and C(12 : 0) 3-OH. The respiratory ubiquinones found in strain LC6(T) were Q-9 (97 %) and Q-8 (3 %). Strain LC6(T) was aerobic, heterotrophic, and able to utilize various carbohydrates and other substrates as carbon source. The G+C content of the genomic DNA of strain LC6(T) was 52.5 mol%. The organism was able to grow at pH 6.0-11.0 (optimum, pH 7.0-8.0), at 4-45 degrees C (optimum, 30-35 degrees C) and in the presence of 0.5-20 % (w/v) NaCl (optimum, 1-3 %, w/v). Based on 16S rRNA gene sequence analysis, strain LC6(T) was most closely related to Halomonas hydrothermalis DSM 15725(T) and Halomonas venusta DSM 4743(T) (98.8 % similarity), followed by Halomonas aquamarina DSM 30161(T), Halomonas axialensis DSM 15723(T) and Halomonas meridiana DSM 5425(T) (98.4 %). However, levels of DNA-DNA relatedness between strain LC6(T) and the above type strains were low (<31 %). Strain LC6(T) resembled recognized Halomonas species with respect to various physiological, biochemical and nutritional characteristics. Combined phenotypic data and DNA-DNA hybridization data supported the conclusion that strain LC6(T) represents a novel species of the genus Halomonas, for which the name Halomonas andesensis is proposed. The type strain is LC6(T) (=CCUG 54844(T)=LMG 24243(T)=DSM 19434(T)).