Paracoccus everestensis sp. nov., a novel bacterium with great antioxidant capacity isolated from the north slope of Mount Everest

Abstract

A bacterial strain, designated S8-55T, was isolated from moraine samples collected from the north slope of Mount Everest at an altitude of 5 500 m above sea level. The purpose of this study was to describe a novel species and its characteristics, through genome sequencing and analysis of the relationship between the members of the genus Paracoccus , and explore the antioxidant capacity of strain S8-55T. The polyphasic study confirmed the affiliation of strain S8-55T with the genus Paracoccus . Strain S8-55T was aerobic, Gram-negative and oxidase- and catalase positive. Cells were orange-pigmented, ellipsoid and had no spore formation, no flagella and no motility. Strain S8-55T grow at 10–37 °C, pH 7–11 and without NaCl. Ubiquinone 10 was its predominant respiratory menaquinone. The polar lipids of strain S8-55T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified phospholipid, an unidentified aminolipid and three unidentified lipids. Its major fatty acids were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The G+C content was 64.3 mol%. The phylogenetic analysis based on the 16S rRNA sequence showed that strain S8-55T was closely related to Paracoccus angustae E6T (97.9 %), Paracoccus aerius 011410T (97.9 %) and Paracoccus hibisci THG-T2.8T (97.8 %). The average nucleotide identity values among strain S8-55T and P. angustae CCTCC AB 2015056T, P. aerius KCTC 42845T and P. hibisci CCTCC AB 2016181T were 84.1, 84.5 and 76.3 %, respectively. The genome of strain S8-55T contained antioxidant genes such as oxyR, recD, katE, recD and rpoH. Based on its morphological, physiological and chemical taxonomic characteristics, strain S8-55T (=JCM 35 227T=GDMCC 1.3026T) should be classified as a novel species of the genus Paracoccus with the proposed name Paracoccus everestensis sp. nov.

A review of natural astaxanthin production in a circular bioeconomy context using Paracoccus carotinifaciens

“…The genus Paracoccus is an aerobic Gram-negative, urease-negative, and oxidase/catalase-positive bacterium that revealed a significant metabolic versatility (Zhao et al, 2022). Phylogenetically, the genus Paracoccus belongs to the phylum Proteobacteria, class Alphaproteobacteria, order Rhodobacterales, family Rhodobacteraceae, that contain more than 96 recognized species from 1969 to 2022 (Cui et al, 2022;Davis et al, 1969). The name Paracoccus derives from the Greek 'Para' (alongside of, resembling) and Latin 'coccus' (grain, berry) (Davis et al, 1969).…”