title: Metabolic traits of an uncultured archaeal lineage--MSBL1--from brine pools of the Red Sea.
abstract: The candidate Division MSBL1 (Mediterranean Sea Brine Lakes 1) comprises a monophyletic group of uncultured archaea found in different hypersaline environments. Previous studies propose methanogenesis as the main metabolism. Here, we describe a metabolic reconstruction of MSBL1 based on 32 single-cell amplified genomes from Brine Pools of the Red Sea (Atlantis II, Discovery, Nereus, Erba and Kebrit). Phylogeny based on rRNA genes as well as conserved single copy genes delineates the group as a putative novel lineage of archaea. Our analysis shows that MSBL1 may ferment glucose via the Embden-Meyerhof-Parnas pathway. However, in the absence of organic carbon, carbon dioxide may be fixed via the ribulose bisphosphate carboxylase, Wood-Ljungdahl pathway or reductive TCA cycle. Therefore, based on the occurrence of genes for glycolysis, absence of the core genes found in genomes of all sequenced methanogens and the phylogenetic position, we hypothesize that the MSBL1 are not methanogens, but probably sugar-fermenting organisms capable of autotrophic growth. Such a mixotrophic lifestyle would confer survival advantage (or possibly provide a unique narrow niche) when glucose and other fermentable sugars are not available.
authors.affiliation: Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Romano
authors.initials: R
authors.lastname: Mwirichia
authors.affiliation: Computational Bioscience Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Intikhab
authors.initials: I
authors.lastname: Alam
authors.affiliation: Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Mamoon
authors.initials: M
authors.lastname: Rashid
authors.affiliation: Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Manikandan
authors.initials: M
authors.lastname: Vinu
authors.affiliation: Computational Bioscience Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Wail
authors.initials: W
authors.lastname: Ba-Alawi
authors.affiliation: Computational Bioscience Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Allan
authors.initials: A
authors.lastname: Anthony Kamau
authors.affiliation: Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: David
authors.initials: D
authors.lastname: Kamanda Ngugi
authors.affiliation: German Collection for Microorganisms and Cell Cultures GmbH (DSMZ), Inhoffenstraße 7b, 38124 Braunschweig, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Göker
authors.affiliation: School of Biology, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Klenk
authors.affiliation: Computational Bioscience Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Bajic
authors.affiliation: Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Stingl
mesh_terms: D001105:Archaea / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D001692:Biological Transport; D050260:Carbohydrate Metabolism; D004734:Energy Metabolism; D020745:Genome, Archaeal; D023281:Genomics / Q000379:methods; D005943:Gluconeogenesis; D006019:Glycolysis; D019156:Indian Ocean; D010802:Phylogeny; D019655:Quantitative Trait, Heritable; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012492:Salts; D017422:Sequence Analysis, DNA; D013312:Stress, Physiological
chemical_list: D012336:RNA, Ribosomal, 16S; D012492:Salts; C017082:brine