Walz J, Koster A J, Tamura T, Baumeister W
Department of Molecular Structural Biology, Max-Planck-Institut für Biochemie, Martinsried, 82152, Germany.
J Struct Biol. 1999 Dec 1;128(1):65-8. doi: 10.1006/jsbi.1999.4169.
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.
嗜热栖热菌的三角蛋白酶在蛋白酶体的“下游”发挥作用；它与其氨肽酶辅因子共同作用，将蛋白酶体产生的肽转化为游离氨基酸。三角蛋白酶的基本功能单位是由121 kDa亚基组成的同型六聚体，其中20个可以进一步组装形成分子量为14.6 MDa的二十面体衣壳。我们利用电子冷冻显微镜确定了三角蛋白酶衣壳的结构，分辨率达到1.3 nm。
