C型葡萄球菌肠毒素的结晶及初步X射线衍射分析

Crystallization and preliminary X-ray diffraction analysis of staphylococcal enterotoxin type C.

作者信息

Bohach G A, Chi Y I, Stauffacher C V

机构信息

Department of Bacteriology and Biochemistry, University of Idaho, Moscow 83843.

出版信息

Proteins. 1992 Apr;13(2):152-7. doi: 10.1002/prot.340130208.

DOI:10.1002/prot.340130208

PMID:1620697

Abstract

The Type C staphylococcal enterotoxin produced by Staphylococcus aureus strain FRI-909 has been crystallized using a combination of two precipitants, ammonium sulfate and polyethylene glycol 400, with the addition of small amounts of detergent. Two related crystal forms have been obtained, one triclinic, and one tetragonal, both with one toxin molecule per asymmetric unit. These crystals are stable for at least 75 hr in the X-ray beam and diffract to at least 2.2 and 2.6 A, respectively. The triclinic crystals have unit cell parameters a = 38.5 A, b = 43.7 A, c = 36.9 A, and interaxial angles alpha = 99.9 degrees, beta = 95.8 degrees, and gamma = 98.5 degrees. The tetragonal crystals are of space group P4(1)22 with unit cell parameters a = 43.4 A and c = 278.0 A.

摘要

金黄色葡萄球菌FRI - 909菌株产生的C型葡萄球菌肠毒素已通过硫酸铵和聚乙二醇400这两种沉淀剂的组合，并添加少量去污剂进行了结晶。已获得两种相关的晶体形式，一种是三斜晶系，一种是四方晶系，每个不对称单元均含有一个毒素分子。这些晶体在X射线束中至少稳定75小时，衍射分辨率分别至少达到2.2 Å和2.6 Å。三斜晶系晶体的晶胞参数为a = 38.5 Å，b = 43.7 Å，c = 36.9 Å，轴间角α = 99.9°，β = 95.8°，γ = 98.5°。四方晶系晶体属于空间群P4(1)22，晶胞参数为a = 43.4 Å和c = 278.0 Å。