Croceicoccus hydrothermalis sp. nov., isolated from shallow-sea hydrothermal system off Kueishantao Island

Abstract

A Gram-stain-negative, strictly aerobic, non-motile, ovoid or short-rod shaped, orange-pigmented bacterial strain, designated as strain JLT1T, was isolated from seawater of the shallow-sea hydrothermal system, near Kueishantao Islet. Growth was observed at 5–45°C (optimum, 30 °C) and pH 5.0–11.0 (optimum, pH 7.0). The salinity range for growth was 0–12 % (optimum, 2–4 %) (w/v) NaCl. JLT1T contained ubiquinone-10 as the main respiratory quinone. Iso-C12 : 0, summed feature 3 (C16 : 1ω7c/ω6c) and summed feature 8 (C18 : 1ω6c/ω7c) were identified as the major cellular fatty acids. Polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unidentified phospholipids, eight unidentified glycolipids and an unidentified lipid. The 16S rRNA gene of JLT1T shared the greatest similarity (96.31 %) with those of Croceicoccus pelagius Ery9T and Croceicoccus ponticola GM-16T. The draft genome size of JLT1T is 3.56 Mb, with 3578 potential genes and a genomic DNA G+C content of 63.24 mol %. Average nucleotide identity and digital DNA–DNA hybridization values of JLT1T compared with C. pelagius Ery9T, C. ponticola GM-16T, Croceicoccus sediminis S2-4-2T, Croceicoccus mobilis Ery22T and Croceicoccus marinus E4A9T were 74.5, 73.9, 74.4, 74.3 and 74.8 % and 20.6, 19.2, 20.0, 20.5 and 19.8%, respectively. On the basis of these phylogenetic, chemotaxonomic and phenotypic features, JLT1T is concluded to represent a novel species of the genus Croceicoccus , for which the name Croceicoccus hydrothermalis sp. nov. is proposed. The type strain is JLT1T (=CGMCC 1.15786T =JCM 31508T).

Genomic and phenotypic characterization of 26 novel marine bacterial strains with relevant biogeochemical roles and widespread presence across the global ocean

“…Strain F390 T groups close to Croceicoccus hydrothermalis JLT1 T in the same clade as the type species, Croceicoccus marinus ( Xu et al, 2009 ; Figure 1 ). The G + C content is more similar between strain F390 T (60.7 mol%) and C. hydrothermalis (63.2 mol%; Chen et al, 2022 ) than with C. marinus (71.5 mol%), and the same trend applies for their polar lipids ( Supplementary Table S8 ). Contrary to strain F390 T and C. hydrothermalis , C. marinus is motile.…”

Isolation and Cultivation of Carotenoid-Producing Strains from Tidal Flat Sediment and Proposal of Croceibacterium aestuarii sp. nov., a Novel Carotenoid-Producing Species in the Family Erythrobacteraceae

“…However, due to the low bootstrap value and limited recovery nodes, it is challenging to establish conclusive relationships between Croceibacterium species using the 16S ribosomal RNA gene-based phylogeny. Hence, it was imperative to construct a more robust phylogenomic tree to elucidate its evolutionary association with Croceibacterium species, as performed in other Erythrobacteraceae genera recently [23,[51][52][53][54][55][56][57][58][59][60][61].…”