6RTA

Tetragonal lysozyme grown with 300g/L Ficoll

6RTA の概要

• エントリーDOI: 10.2210/pdb6rta/pdb
• 関連するPDBエントリー: 6RT1 6RT3 6RT9
• 分子名称: Lysozyme C, CHLORIDE ION, SODIUM ION, ... (4 entities in total)
• 機能のキーワード: glycoside hydrolase, hydrolase
• 由来する生物種: Gallus gallus (Chicken)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 14425.06

構造登録者

Pereira, P.J.B.,Ferreira, C.,Martins, P.M. (登録日: 2019-05-22, 公開日: 2019-06-26, 最終更新日: 2024-11-20)

主引用文献

Ferreira, C.,Pinto, M.F.,Macedo-Ribeiro, S.,Pereira, P.J.B.,Rocha, F.A.,Martins, P.M.
Protein crystals as a key for deciphering macromolecular crowding effects on biological reactions.
Phys Chem Chem Phys, 22:16143-16149, 2020

PubMed Abstract: When placed in the same environment, biochemically unrelated macromolecules influence each other's biological function through macromolecular crowding (MC) effects. This has been illustrated in vitro by the effects of inert polymers on protein stability, protein structure, enzyme kinetics and protein aggregation kinetics. While a unified way to quantitatively characterize MC is still lacking, we show that the crystal solubility of lysozyme can be used to predict the influence of crowding agents on the catalytic efficiency of this enzyme. In order to capture general enthalpic effects, as well as hard entropic effects that are specific of large molecules, we tested sucrose and its cross-linked polymer Ficoll-70 as additives. Despite the different conditions of pH and ionic strength adopted, both the crystallization and the enzymatic assays point to an entropic contribution of approximately -1 kcal mol-1 caused by MC. Our results demonstrate that the thermodynamic activity of proteins is markedly increased by the reduction of accessible volume caused by the presence of macromolecular cosolutes. Unlike what is observed in protein folding studies, this MC effect cannot be reproduced using equivalent concentrations of monomeric crowding units. Applicable to any crystallizable protein, the thermodynamic interpretation of MC based on crystal solubility is expected to help in elucidating the full extent and importance of hard-type interactions in the crowded environment of the cell.

PubMed: 32638771
DOI: 10.1039/d0cp02469d

実験手法

X-RAY DIFFRACTION (1.8 Å)