Control of protein crystal nucleation around the metastable liquid-liquid phase boundary
Control of protein crystal nucleation around the metastable liquid-liquid phase boundary
复制标题
DOI：
10.1073/pnas.110000497
复制
发表时间：
2000-06-06
影响因子：
11.1
通讯作者：
Vekilov, PG
中科院分区：
文献类型：
--
作者：
Galkin, O;Vekilov, PG
增强或抑制蛋白质晶体成核的能力为各种基础和应用领域提供了机会，包括蛋白质晶体学、蛋白质晶体药物的生产、蛋白质分离和蛋白质冷凝病的治疗。在此，我们表明溶菌酶晶体的均匀成核速率在蛋白质溶液相图中隐藏在液相线（溶解度）线以下的液-液相边界附近达到最大值。我们发现甘油和聚乙二醇（不与蛋白质特异性结合）改变了这一相边界，并显著抑制或提高了晶体成核速率，尽管聚乙二醇在相图上的作用与成核动力学之间没有简单的相关性。这种控制机制不需要改变溶液的蛋白质浓度、酸度和离子性。两种添加剂对相图的影响很大程度上取决于它们的浓度，这为进一步调整成核速率提供了机会。
The capability to enhance or suppress the nucleation of protein crystals opens opportunities in various fundamental and applied areas, including protein crystallography, production of protein crystalline pharmaceuticals, protein separation, and treatment of protein condensation diseases. Herein, we show that the rate of homogeneous nucleation of lysozyme crystals passes through a maximum in the vicinity of the liquid-liquid phase boundary hidden below the liquidus (solubility) line in the phase diagram of the protein solution. We found that glycerol and polyethylene glycol (which do not specifically bind to proteins) shift this phase boundary and significantly suppress or enhance the crystal nucleation rates, although no simple correlation exists between the action of polyethylene glycol on the phase diagram and the nucleation kinetics. The control mechanism does not require changes in the protein concentration, acidity, and ionicity of the solution. The effects of the two additives on the phase diagram strongly depend on their concentration, which provides opportunities for further tuning of nucleation rates.