Seven novel halophilic archaeal strains DYHT-AS-1, GDY60, TS25, XH63, SHR40, SYNS179, and ZY30 were isolated from tidal flat, saline lakes, marine solar saltern and coarse sea salts from different regions of China. Metagenomic and amplicon analyses indicated that the abundance of these seven strains in respective habitats was low. Phylogenetic and comparative genomic analyses indicated that strains DYHT-AS-1, GDY60, TS25, and XH63 formed a tight cluster with Halosimplex species, exhibiting high 16S rRNA gene sequence similarity (90.
View Article and Find Full Text PDFHalophilic aminopeptidases with broad substrate specificity represent valuable biocatalysts for promoting protein hydrolysis in high-salt fermented foods. In this study, an M42 aminopeptidase from the halophilic archaeon, Haladaptatus litoreus, was identified and designated as AP. The optimal reaction conditions for AP were 2-2.
View Article and Find Full Text PDFA new family related to the family Haloarculaceae was proposed and the genus Actinarchaeum was merged into the genus Halocatena through phylogenetic, phylogenomic, and comparative genomic analyses. Four strains KK48, YCN56, SYNS191, and SYNS196 with new taxonomic status were isolated from inland saline lakes and a marine solar saltern. According to the comparison of 16S rRNA gene and rpoB' gene sequences, strains KK48, YCN56, SYNS191, and SYNS196 showed high sequence similarities to the genera Salinibaculum and Salinirubellus, respectively.
View Article and Find Full Text PDFFour halophilic archaeal strains were isolated from sea salt and a saline lake in China. Based on phylogenetic and phylogenomic analyses, the four strains are related to the genera of Halobellus, Halobaculum, and Halorarum within the family Haloferacaceae. The four strains possess genes responsible for carotenoid synthesis, maintenance of a high internal salt concentration, as well as diverse enzymes with biotechnological potential.
View Article and Find Full Text PDFFour novel halophilic archaeal strains CGA53, CG83, FCH27, and SEDH24 were isolated from a soda lake and two saline lakes in China, respectively. Strain CGA53 showed the highest 16S rRNA gene similarity (92.6%) to Salinilacihabitans rarus AD-4, and the other three strains were found to be related to Halalkalicoccus species with similarities of 97.
View Article and Find Full Text PDFThe current representatives of the family Natrialbaceae within the class Halobacteria were subjected to phylogenetic, phylogenomic, and comparative genomic analyses. The current species of Halobiforma and Halomontanus were found to be related to those of Natronobacterium and Natronoglomus, respectively. According to the cutoff value of average amino acid identity (AAI) (≤ 76%) proposed to differentiate genera within the family Natrialbaceae, Halobiforma, and Natronoglomus should be merged with Natronobacterium and Halomontanus, respectively.
View Article and Find Full Text PDFFEMS Microbiol Lett
January 2024
Five halophilic archaeal strains, XH8T, CK5-1T, GDY1T, HW8-1T, and XH21T, were isolated from commercial coarse salt produced in different regions of China. Their 16S rRNA and rpoB' gene sequences indicated that four of the strains (CK5-1T, GDY1T, HW8-1T, and XH21T) represent distinct species within the genus Haloplanus (family Haloferacaceae), while strain XH8T represents a novel genus within the same family. These assignments were supported by phylogenetic and phylogenomic analyses, which showed that strains CK5-1T, GDY1T, HW8-1T, and XH21T cluster with the current species of the genus Haloplanus, while strain XH8T forms a separate branch from the genus Haloplanus.
View Article and Find Full Text PDFSalt-tolerant proteases with remarkable stability are highly desirable biocatalysts in the salt-fermented food industry. In this study, the undigested autocleavage product of HlyA (halolysin A), a low-salt adapted halolysin from halophilic archaeon Halococcus salifodinae, was investigated. HlyA underwent autocleavage of its C-terminal extension (CTE) at temperatures over 40 °C or NaCl concentrations below 2 M to yield HlyAΔCTE.
View Article and Find Full Text PDFHaloarchaea with the capacity to degrade alkanes is promising to deal with petroleum pollution in hypersaline environments. However, only a limited number of haloarchaeal species are investigated, and their pathway and mechanism for alkane degradation remain unclear. In this study, Halogranum rubrum RO2-11, a haloarchaeal strain, verified the ability to degrade kerosene and hexadecane in 184 g/L NaCl, with 53% and 52% degradation rates after 9 and 4 days, respectively.
View Article and Find Full Text PDFJ Agric Food Chem
March 2024
Histamine, found abundantly in salt-fermented foods, poses a risk of food poisoning. , a halophilic archaeon isolated from a salt lake, displayed a strong histamine degradation ability. Its histamine oxidase (HOD) gene was identified ().
View Article and Find Full Text PDFAntonie Van Leeuwenhoek
March 2024
Int J Syst Evol Microbiol
March 2024
Halophilic archaea of the class are the most salt-requiring prokaryotes within the domain . In 1997, minimal standards for the description of new taxa in the order were proposed. From then on, the taxonomy of the class provides an excellent example of how changing concepts on prokaryote taxonomy and the development of new methods were implemented.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
January 2024
Int J Syst Evol Microbiol
January 2024
Int J Syst Evol Microbiol
November 2023
Two halophilic archaeal strains, ZS-10 and GSL13, were isolated from the Zhoushan marine saltern in Zhejiang, and an inland saline soil from the Tarim Basin, Xinjiang, PR China, respectively. The cells of strain ZS-10 were pleomorphic while those of strain GSL13 were rod-shaped. Both of them stained Gram-negative and formed red-pigmented colonies on agar plates and their cells lysed in distilled water.
View Article and Find Full Text PDFExtremophiles
October 2023
A single extremely halophilic strain was isolated from salt brine produced when a fresh water lake flooded a large salt mine located beneath the lake. The water that entered this mine contained less than 0.34 M NaCl, but over time, this sealed brine became saturated by Cenozoic age salt (121-125 million-year BCE).
View Article and Find Full Text PDFInt J Syst Evol Microbiol
September 2023