Optimization of salt concentration in PEG-based crystallization solutions

被引：15

作者：

Yamanaka, Mari ^{[1
]}

Inaka, Koji ^{[2
]}

Furubayashi, Naoki ^{[2
]}

Matsushima, Masaaki ^{[3
]}

Takahashi, Sachiko ^{[1
]}

Tanaka, Hiroaki ^{[1
]}

Sano, Satoshi ^{[4
]}

Sato, Masaru ^{[4
]}

Kobayashi, Tomoyuki ^{[4
]}

Tanaka, Tetsuo ^{[4
]}

机构：

[1] Confocal Sci Inc, Tokyo, Japan

[2] Maruwa Foods & Biosci Inc, Nara, Japan

[3] Aino Gakuin Coll, Osaka, Japan

[4] Japan Aerosp Explorat Agcy, Chofu, Tokyo, Japan

来源：

JOURNAL OF SYNCHROTRON RADIATION | 2011年 / 18卷

关键词：

protein crystallization; optimization; salt concentration; polyethylene glycol; ionic strength; PROTEIN CRYSTALLIZATION;

D O I：

10.1107/S0909049510035995

中图分类号：

TH7 [仪器、仪表];

学科分类号：

0804 ; 080401 ; 081102 ;

摘要：

Although polyethylene glycol (PEG) is the most widely used precipitant in protein crystallization, the concentration of co-existing salt in the solution has not been well discussed. To determine the optimum salt concentration range, several kinds of protein were crystallized in a 30% PEG 4000 solution at various NaCl concentrations with various pH levels. It was found that, if crystallization occurred, the lowest effective salt concentration depended on the pH of the protein solution and the pI of the protein molecule; that is, higher salt concentrations were required for crystal growth if the difference between pH and pI was increasing. The linear relationship between the charge density of the protein and the ionic strength of the crystallization solution was further verified. These results suggested that the lowest effective concentration of salt in a crystallization solution can be predicted before performing crystallization experiment. Our results can be a tip for tuning crystallization conditions by the vapor-diffusion method.

引用

页码：84 / 87

页数：4

共 9 条

[1] Colloidal approach analysis of the Marseille protein crystallization database for protein crystallization strategies [J].