Purification, crystallization and preliminary X-ray diffraction analysis of saxthrombin, a thrombin-like enzyme from Gloydius saxatilis venom.
The snake-venom thrombin-like enzymes (SVTLEs) are a class of serine proteinases that show fibrinogen-clotting and esterolytic activities. Most TLEs convert fibrinogen to fibrin by releasing either fibrinopeptide A or fibrinopeptide B and cannot activate factor XIII. The enzymes hydrolyze fibrinogen to produce non-cross-linked fibrins, which are susceptible to the lytic action of plasmin. Because of these physiological properties, TLEs have important medical applications in myocardial infarction, ischaemic stroke and thrombotic diseases. Here, a three-step chromatography procedure was used to purify saxthrombin (AAP20638) from Gloydius saxatilis venom to homogeneity. Its molecular weight is about 30 kDa as estimated by SDS-PAGE. A saxthrombin crystal was obtained using the hanging-drop vapour-diffusion method and diffracted to a resolution limit of 1.43 A. The crystal belongs to space group C2, with unit-cell parameters a = 97.23, b = 52.21, c = 50.10 A, beta = 96.72 degrees , and the Matthews coefficient (V(M)) was calculated to be 2.13 A(3) Da(-1) with one molecule in the asymmetric unit.
Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, People's Republic of China.
Wenqing
W
Wei
Wei
W
Zhao
Xiaoping
X
Wang
Maikun
M
Teng
Liwen
L
Niu
D000818:Animals; D003460:Crystallization; D008969:Molecular Sequence Data; D012910:Snake Venoms / Q000737:chemistry* / Q000302:isolation & purification; D013917:Thrombin / Q000737:chemistry* / Q000302:isolation & purification; D014961:X-Ray Diffraction
D012910:Snake Venoms; D013917:Thrombin