کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8407303 1544988 2014 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Fixed charges in the gel matrix of sensor chips and dissociation in diffusion gradients influence the detection of fast protein-protein interactions
ترجمه فارسی عنوان
اتمام ثابت در ماتریس ژل تراشه های سنسور و جداسازی در شیوه های نفوذ بر تشخیص پروتئین و پروتئین های سریع
کلمات کلیدی
ثابت اتصال مهار رقابت رزونانس پلاسما سطحی، ماتریس ژل شارژ، تعامل الکترواستاتیک، پتانسیل دونان، جدایی ناشی از حمل و نقل جرم،
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات مدل‌سازی و شبیه سازی
چکیده انگلیسی
In molecular interaction studies based on surface plasmon resonance (SPR) measurements, the ligand is often immobilized in a thin carboxydextran gel matrix. Here we investigated the influence of the charged gel on the results of such SPR measurements. At physiological ionic strength, analytes with a net charge of more than about 5 are considerably enriched or depleted due to the Donnan potential under commonly applied experimental conditions. Below physiological ionic strength, enrichment was found to be even stronger than predicted by Donnan theory. The influence of the gel matrix on the apparent binding is prevented in competition experiments, in which SPR measurements are only used to discriminate between free and complexed analyte while the interaction between analyte and ligand is studied in solution. However, if the analyte-ligand interaction is very fast, thermodynamic equilibrium is disturbed near the interface where free analyte binds to the immobilized ligand due to mass transport limitation. Consequently, the soluble analyte-ligand complex dissociates, which results in an overestimation of free analyte. In experiments of calmodulin binding to fragments of the KCNH1 ion channel protein this mass-transport-induced dissociation led to a systematic underestimation of the affinity. We conclude that the insufficient discrimination between the true analyte-ligand binding and the complex interactions of the analyte with the gel phase may result in systematic errors. The theoretical framework for recognizing and avoiding such errors is provided.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biosystems - Volume 116, February 2014, Pages 27-35
نویسندگان
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