کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10843929 1069297 2005 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Expression of G protein coupled receptors in a cell-free translational system using detergents and thioredoxin-fusion vectors
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Expression of G protein coupled receptors in a cell-free translational system using detergents and thioredoxin-fusion vectors
چکیده انگلیسی
In Escherichia coli and other cell-based expression systems, there are critical difficulties in synthesizing membrane proteins, such as the low protein expression levels and the formation of insoluble aggregates. However, structure determinations by X-ray crystallography require the purification of milligram quantities of membrane proteins. In this study, we tried to solve these problems by using cell-free protein expression with an E. coli S30 extract, with G protein coupled receptors (GPCRs) as the target integral membrane proteins. In this system, the thioredoxin-fusion vector induced high protein expression levels as compared with the non-fusion and hexa-histidine-tagged proteins. Two detergents, Brij35 and digitonin, effectively solubilized the produced GPCRs, with little or no effect on the protein yields. The synthesized proteins were detected by Coomassie brilliant blue staining within 1 h of reaction initiation, and were easily reconstituted within phospholipid vesicles. Surprisingly, the unpurified, reconstituted thioredoxin-fused receptor proteins had functional activity, in that a specific affinity binding value of an antagonist was obtained for the receptor. This cell-free translation system (about 1 mg/ml of reaction volume for 6-8 h) has biophysical and biochemical advantages for the synthesis of integral membrane proteins.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Protein Expression and Purification - Volume 41, Issue 1, May 2005, Pages 27-37
نویسندگان
, , , , , , , ,