Aquaticitalea lipolytica gen. nov., sp. nov., isolated from Antarctic seawater

Abstract

A Gram-stain-negative, rod-shaped bacterium, designated Ar-125 T , was isolated from Antarctic seawater. It produced carotenoid-like pigments and did not produce Bchl a. Ar-125 T was positive for hydrolysis of DNA, aesculin, gelatin, starch, Tween 40 and Tween 60. The sole respiratory quinone was MK-6. The major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, one unidentified glycolipid and two unidentified lipids. The principal fatty acids were branched-chain fatty acids, including iso-C 15 : 0, iso-C 15 : 1 G, summed feature 3 (iso-C 15 : 0 2-OH and/or C 16 : 1 !7c), iso-C 16 : 0, iso-C 17 : 0 3-OH, iso-C 16 : 0 3-OH and iso-C 15 : 0 3-OH, as well as C 15 : 0 . The genomic DNA G+C content was 31.8 mol%. On the basis of 16S rRNA gene sequence analysis, Ar-125 T is closely related to the species of the genera Bizionia (with 16S rRNA gene pairwise sequence similarity of 93.7-96.5 %), Formosa(94.3-95.8 %), Gaetbulibacter(94.2-95.7 %), Geojedonia(95.5 %), Gelidibacter (93.3-95.4 %), Meridianimaribacter(95.3 %) and Psychroserpens (94.8-95.3 %), of the family Flavobacteriaceae. Phylogenetic analysis indicated that it represented an independent lineage and that the closest relatives were members of the genus Gelidibacter. Differential phenotypic properties and chemotaxonomic differences, together with phylogenetic distinctiveness, revealed that Ar-125 T could be differentiated from members of closely related genera. Therefore, it is proposed that Ar-125 T represents a novel species in a new genus, for which the name Aquaticitalea lipolytica gen. nov., sp. nov. (type strain Ar-125 T =CGMCC 1.15295 T =JCM 30876 T ) is proposed.

Sandaracinobacteroides sayramensis sp. nov., a yellow-pigmented bacterium isolated from lake water

“…The range of NaCl concentration for growth was studied using R2A medium containing 0, 0.5, 1.0, 1.5, 2, 3, 4, 5, 7.5, 10 and 12 NaCl (%, w/v) according to Chen et al [23]. Hydrolysis of soluble starch (1 %, w/v), cellulose (0.1 %, w/v) and 1 % (v/v) Tweens (40, 60, 80) were determined as described by Xamxidin et al [24]. H 2 S production was tested in a liquid medium with added 0.5 % (w/v) thiosulphate.…”

“…Hydrolysis of soluble starch (1 %, w/v), cellulose (0.1 %, w/v) and 1 % (v/v) Tweens (40, 60, 80) were determined as described by Xamxidin et al . [24]. H 2 S production was tested in a liquid medium with added 0.5 % (w/v) thiosulphate.…”

Limnobacter parvuscolonica sp. nov., thiosulfate-oxidizing bacterium isolated from lake water

“…R 2 A containing 0.5% L-tyrosine was used to test the degradation of L-tyrosine. H 2 S production were assayed according to the methods of Xamxidin M et al [15]. Tween 20, 40, 60 and 80 utilizations were tested according to a standard protocol [16].…”

Different co‐occurring bacteria enhance or decrease the growth of the microalga Nannochloropsis sp. CCAP211/78

“…For instance, Kordia algicida was shown to excrete an extracellular protease to lyse algal cells to acquire their dissolved organic carbon (Paul and Pohnert, 2011), and Croceibacter atlanticus was observed to release an unidentified molecule to arrest diatom cell division and increase secretion of organic carbon (van Tol et al, 2017). The closest relative of strain YP206 is Aquaticitalea lipolytica (99% identity of the 16S rRNA gene) that was isolated from Antarctic seawater and known to hydrolyse lipids (Xamxidin et al, 2016). However, when YP206 was co-cultured on agar plates with Nannochloropsis, the growth inhibition observed in liquid culture was not observed (Figs 1 and 2).…”