Molecular dynamic (in silico) modeling of structure-function of glutelin type-B 5-like from proso millet storage protein: effects of temperature and pressure

J Food Sci Technol. 2023 Jan;60(1):114-122. doi: 10.1007/s13197-022-05594-y. Epub 2022 Sep 20.

Abstract

Molecular dynamic (MD) simulation provides an insight into the behavior of a protein under applied processing at the molecular level. The behavior of glutelin type-B 5-like protein, a type of glutelin protein from proso millet was studied, in solution under different temperatures (300, 350, and 400 K) and pressure (1 bar, 3 kbar, and 6 kbar) levels using a molecular dynamics simulation approach. The combined treatment effect (400 K, 6 kbar) increased the compaction of the protein compared to the level at (300 K, 1 bar) as shown by the decreased radius of gyration values from 3.26 to 2.92 nm, decreased solvent accessibility surface area from 327.47 to 311.06 nm2 and decreased volume from 108.35 to 105.04 nm3. The root means square deviation increased with increasing temperature but decreased with increasing pressure while the root means square fluctuations increased significantly with increased in temperature and pressure. A snapshot of the three-dimensional structure of the protein revealed compression of its occluded cavities at higher pressure levels but no obvious disruption to the secondary structure elements of the protein was observed, except for the loss of a few amino acid residues that comprise the secondary structure element.

Supplementary information: The online version contains supplementary material available at 10.1007/s13197-022-05594-y.

Keywords: Molecular dynamic modeling; Proso millet proteins; Structure–function relationship; Three-dimensional structure.