title: Halorhabdus tiamatea: proteogenomics and glycosidase activity measurements identify the first cultivated euryarchaeon from a deep-sea anoxic brine lake as potential polysaccharide degrader.
abstract: Euryarchaea from the genus Halorhabdus have been found in hypersaline habitats worldwide, yet are represented by only two isolates: Halorhabdus utahensis AX-2(T) from the shallow Great Salt Lake of Utah, and Halorhabdus tiamatea SARL4B(T) from the Shaban deep-sea hypersaline anoxic lake (DHAL) in the Red Sea. We sequenced the H. tiamatea genome to elucidate its niche adaptations. Among sequenced archaea, H. tiamatea features the highest number of glycoside hydrolases, the majority of which were expressed in proteome experiments. Annotations and glycosidase activity measurements suggested an adaptation towards recalcitrant algal and plant-derived hemicelluloses. Glycosidase activities were higher at 2% than at 0% or 5% oxygen, supporting a preference for low-oxygen conditions. Likewise, proteomics indicated quinone-mediated electron transport at 2% oxygen, but a notable stress response at 5% oxygen. Halorhabdus tiamatea furthermore encodes proteins characteristic for thermophiles and light-dependent enzymes (e.g. bacteriorhodopsin), suggesting that H. tiamatea evolution was mostly not governed by a cold, dark, anoxic deep-sea habitat. Using enrichment and metagenomics, we could demonstrate presence of similar glycoside hydrolase-rich Halorhabdus members in the Mediterranean DHAL Medee, which supports that Halorhabdus species can occupy a distinct niche as polysaccharide degraders in hypersaline environments.
authors.affiliation: Max Planck Institute for Marine Microbiology, Bremen, Germany; Jacobs University Bremen gGmbH, Bremen, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Werner
authors.forename: Manuel
authors.initials: M
authors.lastname: Ferrer
authors.forename: Gurvan
authors.initials: G
authors.lastname: Michel
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Mann
authors.forename: Sixing
authors.initials: S
authors.lastname: Huang
authors.forename: Silvia
authors.initials: S
authors.lastname: Juarez
authors.forename: Sergio
authors.initials: S
authors.lastname: Ciordia
authors.forename: Juan P
authors.initials: JP
authors.lastname: Albar
authors.forename: María
authors.initials: M
authors.lastname: Alcaide
authors.forename: Violetta
authors.initials: V
authors.lastname: La Cono
authors.forename: Michail M
authors.initials: MM
authors.lastname: Yakimov
authors.forename: André
authors.initials: A
authors.lastname: Antunes
authors.forename: Marco
authors.initials: M
authors.lastname: Taborda
authors.forename: Milton S
authors.initials: MS
authors.lastname: da Costa
authors.forename: Tran
authors.initials: T
authors.lastname: Hai
authors.forename: Frank Oliver
authors.initials: FO
authors.lastname: Glöckner
authors.forename: Olga V
authors.initials: OV
authors.lastname: Golyshina
authors.forename: Peter N
authors.initials: PN
authors.lastname: Golyshin
authors.forename: Hanno
authors.initials: H
authors.lastname: Teeling
mesh_terms: D000222:Adaptation, Physiological; D000693:Anaerobiosis / Q000502:physiology; D005075:Biological Evolution; D017753:Ecosystem; D057075:Enzyme Assays; D020745:Genome, Archaeal; D006026:Glycoside Hydrolases / Q000235:genetics / Q000378:metabolism; D006216:Halobacteriaceae / Q000145:classification / Q000201:enzymology / Q000235:genetics*; D019156:Indian Ocean; D060106:Lakes / Q000382:microbiology; D056186:Metagenomics; D010100:Oxygen / Q000378:metabolism / Q000494:pharmacology; D010802:Phylogeny; D011134:Polysaccharides / Q000378:metabolism*; D055049:Salt Tolerance / Q000235:genetics*; D012965:Sodium Chloride; D014589:Utah; D014871:Water Microbiology
chemical_list: D011134:Polysaccharides; D012965:Sodium Chloride; D006026:Glycoside Hydrolases; D010100:Oxygen