Lysobacter oligotrophicus sp. nov., isolated from an Antarctic freshwater lake in Antarctica

Abstract

A Gram-stain-negative, non-spore-forming, rod-shaped, aerobic bacterium (strain 107-E2 T ) was isolated from freshwater samples containing microbial mats collected at a lake in Skarvsnes, Antarctica (temporary lake name, Lake Tanago Ike). Strain 107-E2T grew between 5 and 25 6C,with an optimum of 23 6C. Moreover, colony formation was observed on agar media even at "5 6C. The pH range for growth was between 6.0 and 9.0, with an optimum of pH 7.0-8.0. The range of NaCl concentration for growth was between 0.0 and 0.5 % (w/v), with an optimum of 0.0 %. No growth was observed in media containing organic compounds at high concentrations, which indicated that strain 107-E2 T was an oligotroph. In the late stationary phase, strain 107-E2 T produced a dark brown water-soluble pigment. Esterase, amylase and protease production was observed. Antimicrobial-lytic activities for Gram-negative bacteria and yeast were observed. Ubiquinone-8 was the major respiratory quinone. The major fatty acids were iso-C 15 : 0 , iso-C 17 : 1 v9c and iso-C 15 : 1 at 5. The G+C content of genomic DNA was 66.1 mol%. Analysis of the 16S rRNA gene sequences revealed that strain 107-E2 T belonged to the genus Lysobacter, and low DNA-DNA relatedness values with closely related species distinguished strain 107-E2

Characterization of water-soluble dark-brown pigment from Antarctic bacterium, Lysobacter oligotrophicus

“…Although it has been known that the pigments are not carotenoids or flexirubins, the pigment has not been identified (26). In the previous study, the production of the pigment by L. oligotrophicus was inhibited by the addition of tyrosinase inhibitor (kojic acid), and the pigment from L. oligotrophicus was expected to be melanin pigment (25). In this study, the dark-brown water-soluble pigment from L. oligotrophicus was identified, and then, the relation between UV irradiation to the cell and production of the pigment was analyzed.…”

“…Among them, an oligotrophic and cold-tolerant bacterium, Lysobacter oligotrophicus, was isolated from the freshwater samples containing microbial mats (25). L. oligotrophicus produces various hydrolases such as protease, amylase and esterase.…”

Lysobacter aestuarii sp. nov., isolated from estuary sediment

“…In addition, all members of the genus Lysobacter are negative for urease activity and indole production and contain ubiquinone 8 (Q-8) as the predominant respiratory quinone, iso-branched fatty acids as the major fatty acids and diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine as the major polar lipids. Most species of the genus Lysobacter except for a few, which were isolated from aquatic habitats (including Antarctic freshwater, wastewater treatment sludge and a deep-sea lake sponge), have been generally found in terrestrial soil (Bae et al, 2005;Romanenko et al, 2008;Fukuda et al, 2013;Ye et al, 2015). A putative novel species of the genus Lysobacter, designated strain S2-C T , was isolated from estuary sediment, which is not a terrestrial habitat, and here we report on its taxonomic position derived from a polyphasic characterization.…”

Lysobacter hymeniacidonis sp. nov., isolated from a crude oil-contaminated marine sponge

“…fr/). Recently, three novel species of the genus, Lysobacter arseniciresistens ZS79 T from iron-mined soil (Luo et al, 2012), Lysobacter oligotrophicus 107-E2 T from an Antarctic freshwater lake (Fukuda et al, 2013) and Lysobacter panacisoli CJ29 T from ginsengsoil (Choi et al, 2014) have been described. Members of the genus were of great potential for the development of biocontrol agents against plant fungal pathogens (Islam et al, 2005;Park et al, 2008) and antibiotic bioactivities against human pathogens (Ahmed et al, 2003;Hashizume et al, 2004).…”