AUTHOR=Sun Ya-Ping , Wang Bei-Bei , Wu Zhang-Ping , Zheng Xi-Wen , Hou Jing , Cui Heng-Lin 

TITLE=Halorarius litoreus gen. nov., sp. nov., Halorarius halobius sp. nov., Haloglomus halophilum sp. nov., Haloglomus salinum sp. nov., and Natronomonas marina sp. nov., extremely halophilic archaea isolated from tidal flat and marine solar salt

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 10 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2023.1105929

DOI=10.3389/fmars.2023.1105929

ISSN=2296-7745

ABSTRACT=Five novel halophilic archaeal strains, named BND22T, ZY10T, ZY41T, ZY58T, and ZY43T, were isolated from the coastal saline sediment of the intertidal zone located in Qingdao and the coarse sea salt produced in the marine solar saltern of Hebei province, China. All these strains were motile, lysed in distilled water, stained Gram-negative, and formed red-pigmented colonies on NHM agar plates. The 16S rRNA gene analysis indicated that strain BDN22T was associated with Salinirubellus salinus ZS-35-S2T (95.2% similarity), strain ZY10T was related to Halosegnis rubeus F17-44T (95.1% similarity), both strains ZY41T and ZY58T were closely related to Haloglomus irregulare F16-60T (98.1% and 98.2% similarities, respectively), and strain ZY43T was close to Natronomonas salina YPL13T (98.0% similarity). Phylogenetic and phylogenomic analyses based on rpoB′ genes and 122 conserved archaeal protein marker genes showed that these strains formed three different branches and clustered tightly with the Haloarculaceae members. Strains BND22T and ZY10T formed two distinct clades separated from Salinirubellus salinus ZS-35-S2T and Halosegnis members, strains ZY41T and ZY58T clustered with Haloglomus irregulare F16-60T, and strain ZY43T gathered with the current members of Natronomonas. The average nucleotide identity (ANI), in silico DNA–DNA hybridization (isDDH), and average amino acid identity (AAI) values of these five strains against closely related species were no more than 91%, 45%, and 92%, respectively, lower than the threshold values for species demarcation, supporting their placements in new taxa. Based on the phenotypic, chemotaxonomic, phylogenetic and phylogenomic properties, these five strains represent five novel taxa of the family Haloarculaceae, Halorarius litoreus gen. nov., sp. nov. (type strain BND22T = CGMCC 1.18780T = JCM 34966T), Halorarius halobius sp. nov. (type strain ZY10T = CGMCC 1.17475T = JCM 34319T), Haloglomus halophilum sp. nov. (type strain ZY41T = CGMCC 1.17030T = JCM 34161T), Haloglomus salinum sp. nov. (type strain ZY58T = CGMCC 1.17216T = JCM 34163T), and Natronomonas marina sp. nov. (type strain ZY43T = CGMCC 1.17202T = JCM 34162T).