title: Trans-cyclohexanediamines prevent thermal inactivation of protein: role of hydrophobic and electrostatic interactions.
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.
authors.affiliation: Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hirano
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hamada
authors.forename: Kentaro
authors.initials: K
authors.lastname: Shiraki
mesh_terms: D000818:Animals; D003514:Cyclohexylamines / Q000494:pharmacology*; D006358:Hot Temperature; D057927:Hydrophobic and Hydrophilic Interactions; D009113:Muramidase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D017510:Protein Folding; D012259:Ribonuclease, Pancreatic / Q000037:antagonists & inhibitors* / Q000737:chemistry; D055672:Static Electricity; D013237:Stereoisomerism
chemical_list: D003514:Cyclohexylamines; C088969:1,4-diaminocyclohexane; C030435:1,2-cyclohexanediamine; D012259:Ribonuclease, Pancreatic; D009113:Muramidase