蓖麻种子中硬脂酰-酰基载体蛋白去饱和酶的初步晶体学数据。

Preliminary crystallographic data for stearoyl-acyl carrier protein desaturase from castor seed.

作者信息

Schneider G, Lindqvist Y, Shanklin J, Somerville C

机构信息

Department of Molecular Biology, Swedish University of Agricultural Sciences, Uppsala.

出版信息

J Mol Biol. 1992 May 20;225(2):561-4. doi: 10.1016/0022-2836(92)90941-c.

DOI:10.1016/0022-2836(92)90941-c

PMID:1593637

Abstract

Recombinant stearoyl-acyl carrier protein desaturase (EC 1.14.99.6) from castor seed has been crystallized with polyethylene glycol 8000 as precipitant. The crystals are orthorhombic, space group P2(1)2(1)2(1) with cell dimensions a = 81.3, b = 146.4 and c = 197.7 A. The observed diffraction pattern extends to at least 2.5 A resolution. Rotation function calculations indicate a non-crystallographic 3-fold rotation axis parallel to the crystallographic a-axis. Perpendicular to this axis, 2-fold rotation axes were found at 30 degrees intervals, i.e. maxima at kappa = 180 degrees, phi = 90 degrees and omega = 30 degrees and 60 degrees, respectively. Together with the packing density of the crystals (Vm = 2.4 A3/Da for n = 6), these results suggest, that the crystal asymmetric unit most likely contains a hexamer of desaturase subunits.

摘要

来自蓖麻籽的重组硬脂酰 - 酰基载体蛋白去饱和酶（EC 1.14.99.6）已用聚乙二醇8000作为沉淀剂进行了结晶。晶体为正交晶系，空间群P2(1)2(1)2(1)，晶胞参数a = 81.3 Å，b = 146.4 Å，c = 197.7 Å。观察到的衍射图谱延伸至至少2.5 Å分辨率。旋转函数计算表明，存在一个与晶轴a平行的非晶体学3次旋转轴。垂直于该轴，每隔30度发现一个2次旋转轴，即分别在κ = 180度、φ = 90度以及ω = 30度和60度处出现最大值。结合晶体的堆积密度（对于n = 6，Vm = 2.4 Å3 / Da），这些结果表明，晶体不对称单元很可能包含去饱和酶亚基的六聚体。