Dynamics of Proteins by Thermal Decay of Free Radicals Induced by Ultraviolet Irradiation. (28th June 2018)

• Record Type: Journal Article
• Authors: Aslanov, Rasim B.; Dashdemirova, Leman M.; Alekperov, Oktay Z.; Abdurahimov, Azad R.; Gasymov, Oktay K.
• Other Names: Severcan Feride Academic Editor.
• Is Part Of: Journal of spectroscopy. Volume 2018(2018)
• Publication Date: 2018-06-28
• Subjects: Spectrum analysis -- Periodicals; 543.505
• DOI: 10.1155/2018/6197636
• Languages: English
• ISSNs: 2314-4920

Abstract

Abstract : The relationship between structure, dynamics, and function of biomolecules is a fundamental interest of biophysics. Protein dynamics drastically vary in temporal and spatial scales. The function of a particular protein determines the significance of a distinct type of dynamics. Here, we investigate the influence of hydration water on the dynamics of a protein called silk fibroin. Particular interest is to investigate the protein dynamics using thermal decay of the free radicals induced by ultraviolet irradiation . The full decay of the free radicals occurs at very wide temperature region (120 K–340 K). Three distinct regions with transition points of ∼135 K, 205 K, and 279 K are apparent in the thermal decay curves of hydrated fibroin samples. The first transition (∼135 K) that leads 2–6% increase of total spins was observed only in the decay curves of fibroin submerged in 40% and 50% glycerol. The second transition (∼205 K) was invariant for all samples, hydrated and dry fibroins. The third transition of 279 K common for all hydrated fibroin samples was shifted about 84 K to a higher temperature of 363 K in dry fibroin. The thermal transitions at 205 K and 279 K are weakly and strongly, respectively, coupled to water molecules. Nature of the free radicals participated in these transitions was identified. The significance of the findings for protein dynamics is discussed.