| 翻訳と辞書 |
| Salt bridge (protein) ： ウィキペディア英語版 |
Salt bridge (protein and supramolecular)
Salt bridges fall into the broader category of noncovalent interactions. A salt bridge is actually a combination of two noncovalent interactions: hydrogen bonding and electrostatic interactions (Figure 1). This is most commonly observed to contribute stability to the entropically unfavorable folded conformation of proteins. Although noncovalent interactions are known to be relatively weak interactions, small stabilizing interactions can add up to make an important contribution to the overall stability of a conformer. Not only are salt bridges found in proteins, but they can also be found in supramolecular chemistry. The thermodynamics of each are explored through experimental procedures to assess the free energy contribution of the salt bridge to the overall free energy of the state.
==Salt bridges found in proteins==
The salt bridge most often arises from the anionic carboxylate (RCOO−) of either aspartic acid or glutamic acid and the cationic ammonium (RNH3+) from lysine or the guanidinium (RNHC(NH2)2+) of arginine (Figure 2).〔 Although these are the most common, other residues with ionizable side chains such as histidine, tyrosine, and serine can also participate, depending on outside factors perturbing their p''K''a's. The distance between the residues participating in the salt bridge is also cited as being important. The distance required is less than 4 Å (400 pm). Amino acids greater than this distance do not qualify as forming a salt bridge. Due to the numerous ionizable side chains of amino acids found throughout a protein, the pH at which a protein is placed is crucial to its stability.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「Salt bridge (protein and supramolecular)」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|