Abstract
A novel pink-pigmented bacterium, designated strain 3D7T, was isolated during an investigation of potential psychrotolerant species from Antarctic soil. Cells of the isolate were observed to be rod-shaped (0.7-0.9 × 1.0-2.2µm), Gram-stain negative and non-motile. It was able to grow at 4-32 °C, pH 7.0-10.0 and in the presence of 0-3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 3D7T belongs to the genus Microvirga and was most closely related to 'Microvirga brassicacearum' CDVBN77T (98.3%), Microvirga subterranea DSM 14364T (96.8%), Microvirga guangxiensis 25BT (96.5%) and Microvirga aerophila DSM 21344T (96.5%). The predominant quinone was ubiquinone 10 (Q-10), and the major fatty acids were summed feature 8 (C18:1ω7c and/or C18:1ω6c) and C19:0 cyclo ω8c. The predominant polar lipids were phosphatidylcholine and phosphatidylethanolamine. The genomic DNA G + C content of strain 3D7T was 63.5mol%. Its genome sequence showed genes encoding phosphatases and lipases. Genetic machinery related to carbohydrate-active enzymes and secondary metabolites were also observed. The average nucleotide identity and digital DNA-DNA hybridization values based on whole genome sequences of strain 3D7T and its closely related species were below the threshold range for species determination. Phenotypic, chemotaxonomic, phylogenetic and genomic analyses suggested that strain 3D7T represents a novel species of the genus Microvirga, for which the name Microvirga antarctica sp. nov. is proposed. The type strain is 3D7T (= CGMCC 1.13821T = KCTC 72465T).
Highlights
To survive in an extremely cold and oligotrophic habitat, Antarctic microorganisms have formed unique physiological and biochemical properties in the long-term natural selection evolution (Niederberger et al 2008)
Based on polyphasic taxonomic characterisation, we propose the description of Microvirga antarctica sp. nov., isolated as a novel psychrotolerant member of the genus Microvirga with phosphatase and lipase activities
The NJ analyses (Fig. 1) showed that strain 3D7T shared a branching node with ‘M. brassicacearum’ CDVBN77T, which was highly consistent with ME tree (Fig. S1) and ML tree (Fig. S2)
Summary
To survive in an extremely cold and oligotrophic habitat, Antarctic microorganisms have formed unique physiological and biochemical properties in the long-term natural selection evolution (Niederberger et al 2008). At the time of writing, the genus Microvirga contains 18 species listed on LPSN (List of Prokaryotic Names with Standing in Nomenclature: www.bacterio.net) with validly published names They are distributed widely in various ecological habitats, such as air (Weon et al 2010), natural, domestic, and contaminated soils (Dahal et al 2017; Tapase et al 2017; Zhang et al 2009; Zhang et al 2019), geothermal water (Kanso et al 2003), Tibet hot spring sediments (Liu et al 2020), human stool (Caputo et al 2016), nodules of native legumes and cowpea (Ardley et al 2012; Radl et al 2017; Safronova et al 2017) and roots of rapeseed plants (Jiménez-Gómez et al 2019). We obtained and analyzed the genome sequence of strain M. antarctica 3D7T, showing its genetic potential for biotechnological industrial application
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
