Macromolecular crowding on Dynamics and Thermodynamic Stability of Heme Proteins
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Date
2018
Authors
Kumar, Rajesh
Kumar, Rajesh
Sharma, Deepak
Garg, Mansi
Kumar, Vinay
Agarwal, Mukesh Chand
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier
Abstract
Structural and molecular properties extracted from circular dichroism (CD), tryptophanfluorescence and 1-anilino-8-napthalene sulfonate (ANS) binding experiments suggest that the high concentration of synthetic crowding agents (dextran 40, dextran70 and ficoll 70) stabilizes and refolds the base-denatured ferricytochrome c (Ferricyt c) and lysozyme (Lyz) at pH 12.9 (±0.1) to molten globule (MG) states (CB-states). These results further revealed that the CB-states resemble the generic properties of MG-states. Thermodynamic analysis of thermal denaturation curves of base-denatured Ferricyt c and Lyz at pH 12.9 (±0.1) under variable concentrations of crowding agents (dextran 40, dextran 70 and ficoll 70) revealed that the crowder presence increases the thermal stability of base-denatured proteins and also prevents the cold denaturation of Ferricyt c. The results further showed that the nature, size and shape of crowder influence the crowding-mediated increase in secondary structure stabilization and thermal stability of base-denatured Ferricyt c and Lyz. Analysis of kinetic and thermodynamic parameters measured for CO association reaction of alkaline ferrocytochrome c (Ferrocyt c) at pH 12.9 (±0.1) under variable concentrations of crowding agents (dextran 40, dextran 70 and ficoll 70) revealed that the crowder presence reduces the level of structural fluctuation of M80-containing Ω-loop that control CO association to alkaline Ferrocyt c.
Description
Keywords
Molten-globule state, Crowding agents, Thermal stability, Cold denaturation, Enthalpy-entropy plot
Citation
Kumar, Rajesh., Kumar, Rajesh., Sharma, Deepak and et. al. (2018) Macromolecular crowding on Dynamics and Thermodynamic Stability of Heme Proteins. Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics. Vol. 1866 (11), PP. https://doi.org/10.1016/j.bbapap.2018.08.012