Döhler Christoph, Zebisch Matthias, Krinke Dana, Robitzki Andrea, Sträter Norbert
Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany.
Division of Molecular Biological-Biochemical Processing Technology, Center for Biotechnology and Biomedicine, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany.
Acta Crystallogr F Struct Biol Commun. 2018 Nov 1;74(Pt 11):696-703. doi: 10.1107/S2053230X18011111. Epub 2018 Oct 16.
Ectonucleotide phosphodiesterase/pyrophosphatase-3 (NPP3, ENPP3) is an ATP-hydrolyzing glycoprotein that is located in the extracellular space. The full-length ectodomain of rat NPP3 was expressed in HEK293S GntI cells, purified using two chromatographic steps and crystallized. Its structure at 2.77 Å resolution reveals that the active-site zinc ions are missing and a large part of the active site and the surrounding residues are flexible. The SMB-like domains have the same orientation in all four molecules in the asymmetric unit. The SMB2 domain is oriented as in NPP2, but the SMB1 domain does not interact with the PDE domain but extends further away from the PDE domain. Deletion of the SMB domains resulted in crystals that diffracted to 2.4 Å resolution and are suitable for substrate-binding studies.
胞外核苷酸磷酸二酯酶/焦磷酸酶-3（NPP3，ENPP3）是一种位于细胞外空间的ATP水解糖蛋白。大鼠NPP3的全长胞外结构域在HEK293S GntI细胞中表达，通过两步色谱法纯化并结晶。其分辨率为2.77 Å的结构显示，活性位点的锌离子缺失，活性位点的大部分和周围残基具有灵活性。在不对称单元的所有四个分子中，类SMB结构域具有相同的取向。SMB2结构域的取向与NPP2中的相同，但SMB1结构域不与PDE结构域相互作用，而是从PDE结构域进一步延伸。删除SMB结构域后得到的晶体衍射分辨率为2.4 Å，适用于底物结合研究。
