title: Primary structure of selected archaeal mesophilic and extremely thermophilic outer surface layer proteins.
abstract: The archaea are recognized as a separate third domain of life together with the bacteria and eucarya. The archaea include the methanogens, extreme halophiles, thermoplasmas, sulfate reducers and sulfur metabolizing thermophiles, which thrive in different habitats such as anaerobic niches, salt lakes, and marine hydrothermals systems and continental solfataras. Many of these habitats represent extreme environments in respect to temperature, osmotic pressure and pH-values and remind on the conditions of the early earth. The cell envelope structures were one of the first biochemical characteristics of archaea studied in detail. The most common archaeal cell envelope is composed of a single crystalline protein or glycoprotein surface layer (S-layer), which is associated with the outside of the cytoplasmic membrane. The S-layers are directly exposed to the extreme environment and can not be stabilized by cellular components. Therefore, from comparative studies of mesophilic and extremely thermophilic S-layer proteins hints can be obtained about the molecular mechanisms of protein stabilization at high temperatures. First crystallization experiments of surface layer proteins under microgravity conditions were successful. Here, we report on the biochemical features of selected mesophilic and extremely archaeal S-layer (glyco-) proteins.
authors.affiliation: Institut für Mikrobiologie und Weinforschung, Johannes Gutenberg-Universität, Mainz, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Claus
authors.forename: Erol
authors.initials: E
authors.lastname: Akça
authors.forename: Tony
authors.initials: T
authors.lastname: Debaerdemaeker
authors.forename: Christine
authors.initials: C
authors.lastname: Evrard
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Declercq
authors.forename: Helmut
authors.initials: H
authors.lastname: König
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D001105:Archaea / Q000737:chemistry / Q000648:ultrastructure; D019843:Archaeal Proteins / Q000737:chemistry* / Q000648:ultrastructure; D017753:Ecosystem; D006358:Hot Temperature; D008565:Membrane Proteins / Q000737:chemistry* / Q000648:ultrastructure; D021382:Protein Sorting Signals / Q000235:genetics; D017433:Protein Structure, Secondary; D016415:Sequence Alignment
chemical_list: D000596:Amino Acids; D019843:Archaeal Proteins; D008565:Membrane Proteins; D021382:Protein Sorting Signals