Trans-cyclohexanediamines prevent thermal inactivation of protein: role of hydrophobic and electrostatic interactions
Atsushi Hirano1, Hiroyuki Hamada, Kentaro Shiraki
1Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
Abstract:
Although solution additives prevent protein misfolding, the mechanism remains elusive. In this paper, we compare the preventive effects of trans-1,2-cyclohexanediamine (1,2-CHDA) and trans-1,4-cyclohexanediamine (1,4-CHDA) on the heat-induced inactivation of ribonuclease A (RNase A) and lysozyme. These additives are more effective in preventing thermal inactivation of the proteins than guanidine (Gdn) and arginine (Arg). The results suggest two possibilities: (i) decrease in the hydrophobic interaction between unfolded protein molecules is indispensable for preventing protein association, and (ii) the electrostatic interaction between additives interacting with the hydrophobic residues of protein molecules plays an important role in preventing thermal inactivation of proteins.
Related Concept Videos
Protein Denaturation
Allosteric Proteins-ATCase
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis pathway,...
Stability of Substituted Cyclohexanes
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
Protein Folding
Protein Folding
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR


