title: Capsids of tricorn protease studied by electron cryomicroscopy.
abstract: Tricorn protease from the archaeon Thermoplasma acidophilum acts "downstream" of the proteasome; in conjunction with its aminopeptidase cofactors it converts peptides generated by the proteasome into free amino acids. The basic functional unit of Tricorn is a homohexamer of the 121-kDa subunit, 20 of which can assemble further to form an icosahedral capsid with a molecular mass of 14.6 MDa. We have used electron cryomicroscopy to determine the structure of the Tricorn capsids to a resolution of 1.3 nm.
authors.affiliation: Department of Molecular Structural Biology, Max-Planck-Institut für Biochemie, Martinsried, 82152, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Walz
authors.forename: A J
authors.initials: AJ
authors.lastname: Koster
authors.forename: T
authors.initials: T
authors.lastname: Tamura
authors.forename: W
authors.initials: W
authors.lastname: Baumeister
mesh_terms: D019843:Archaeal Proteins / Q000648:ultrastructure*; D020285:Cryoelectron Microscopy; D003546:Cysteine Endopeptidases / Q000378:metabolism; D010450:Endopeptidases / Q000648:ultrastructure*; D005583:Fourier Analysis; D007091:Image Processing, Computer-Assisted; D008958:Models, Molecular; D009097:Multienzyme Complexes / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex; D011487:Protein Conformation; D013822:Thermoplasma
chemical_list: D019843:Archaeal Proteins; D009097:Multienzyme Complexes; D010450:Endopeptidases; C102094:tricorn protease; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex