title: Structural Insights into the A1 ATPase from the archaeon, Methanosarcina mazei Gö1.
abstract: The low-resolution structure and overall dimensions of the A(3)B(3)CDF complex of the A(1) ATPase from Methanosarcina mazei Gö1 in solution is analyzed by synchrotron X-ray small-angle scattering. The radius of gyration and the maximum size of the complex are 5.03 +/- 0.1 and 18.0 +/- 0.1 nm, respectively. The low-resolution shape of the protein determined by two independent ab initio approaches has a knob-and-stalk-like feature. Its headpiece is approximately 9.4 nm long and 9.2 nm wide. The stalk, which is known to connect the headpiece to its membrane-bound A(O) part, is approximately 8.4 nm long. Limited tryptic digestion of the A(3)B(3)CDF complex was used to probe the topology of the smaller subunits (C-F). Trypsin was found to cleave subunit C most rapidly at three sites, Lys(20), Lys(21), and Arg(209), followed by subunit F. In the A(3)B(3)CDF complex, subunit D remained protected from proteolysis.
authors.affiliation: Fachbereich Biologie/Chemie, Universität Osnabrück, D-49069 Osnabrück, Germany. ggrueber@biologie.uni-onasbrueck.de
authors.forename: G
authors.initials: G
authors.lastname: Grüber
authors.forename: D I
authors.initials: DI
authors.lastname: Svergun
authors.forename: U
authors.initials: U
authors.lastname: Coskun
authors.forename: T
authors.initials: T
authors.lastname: Lemker
authors.forename: M H
authors.initials: MH
authors.lastname: Koch
authors.forename: H
authors.initials: H
authors.lastname: Schägger
authors.forename: V
authors.initials: V
authors.lastname: Müller
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000378:metabolism; D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry* / Q000378:metabolism; D006868:Hydrolysis; D017020:Methanosarcina / Q000201:enzymology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D012542:Scattering, Radiation; D013329:Structure-Activity Relationship; D014357:Trypsin / Q000378:metabolism; D014965:X-Rays
chemical_list: D019843:Archaeal Proteins; D010446:Peptide Fragments; D014357:Trypsin; D000251:Adenosine Triphosphatases