Capillary zone electrophoresis with optimized temperature control for studying thermal denaturation of proteins at various pH
Capillary electrophoresis (CE) was used to analyze the thermal denaturation of bovine β‐lactoglobulin at different pH. This model protein exhibits complex pH‐ and temperature association/dissociation dependence balances in its quaternary structure. The study was possible after modification and impro...
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Published in | Electrophoresis Vol. 20; no. 7; pp. 1586 - 1594 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
Hoboken
Wiley Subscription Services, Inc., A Wiley Company
01.06.1999
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Subjects | |
Online Access | Get full text |
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Summary: | Capillary electrophoresis (CE) was used to analyze the thermal denaturation of bovine β‐lactoglobulin at different pH. This model protein exhibits complex pH‐ and temperature association/dissociation dependence balances in its quaternary structure. The study was possible after modification and improvement of a capillary electrophoresis apparatus. The improvement allowed both efficient control (temperature fluctuations <0.05oC) and accurate measurement of the temperature (± 0.1oC) within the capillary cartridge. CE allowed the thermodynamic parameters of β‐lactoglobulin thermal denaturation to be estimated. The transition temperature, Tm, was determined at acidic, neutral and alkaline pH. Van't Hoff analysis was performed through direct measurement of native and unfolded protein populations in the slow‐time regime. This allowed estimation of thermodynamic parameters (ΔH, ΔS, ΔCp). Finally, the stability curve, i.e., the temperature dependence of the free energy change (ΔG) of protein unfolding was drawn. The accuracy of the parameters values compares with parameters obtained by calorimetric measurements. The available parameters and the requirement of minute amount of protein sample are of potential interest in the field of protein engineering and biological pharmaceuticals. Accordingly, CE can be proposed as a convenient tool to study protein stability and denaturation processes. |
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Bibliography: | ArticleID:ELPS1586 ark:/67375/WNG-BWNG854S-2 istex:03E364248C04C125E3E6EEFFE1F6293C4B892F71 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0173-0835 1522-2683 |
DOI: | 10.1002/(SICI)1522-2683(19990601)20:7<1586::AID-ELPS1586>3.0.CO;2-3 |