Department of Physics, Chalmers University of Technology, Gothenburg SE-412 96, Sweden.
J Phys Chem B. 2024 May 23;128(20):4922-4930. doi: 10.1021/acs.jpcb.4c00022. Epub 2024 May 11.
The disaccharide trehalose is generally acknowledged as a superior stabilizer of proteins and other biomolecules in aqueous environments. Despite many theories aiming to explain this, the stabilization mechanism is still far from being fully understood. This study compares the stabilizing properties of trehalose with those of the structurally similar disaccharide sucrose. The stability has been evaluated for the two proteins, lysozyme and myoglobin, at both low and high temperatures by determining the glass transition temperature, , and the denaturation temperature, . The results show that the sucrose-containing samples exhibit higher than the corresponding trehalose-containing samples, particularly at low water contents. The better stabilizing effect of sucrose at high temperatures may be explained by the fact that sucrose, to a greater extent, binds directly to the protein surface compared to trehalose. Both sugars show elevation with an increasing sugar-to-protein ratio, which allows for a more complete sugar shell around the protein molecules. Finally, no synergistic effects were found by combining trehalose and sucrose. Conclusively, the exact mechanism of protein stabilization may vary with the temperature, as influenced by temperature-dependent interactions between the protein, sugar, and water. This variability can make trehalose to a superior stabilizer under some conditions and sucrose under others.
海藻糖是一种公认的优越的稳定剂，能稳定水相环境中的蛋白质和其他生物分子。尽管有许多理论试图解释这种现象，但稳定机制仍远未完全理解。本研究比较了海藻糖与结构相似的二糖蔗糖的稳定特性。通过测定玻璃化转变温度和变性温度，评估了两种蛋白质（溶菌酶和肌红蛋白）在低温和高温下的稳定性。结果表明，含有蔗糖的样品比含有相应海藻糖的样品具有更高的玻璃化转变温度，特别是在低含水量时。蔗糖在高温下具有更好的稳定效果，可能是因为与海藻糖相比，蔗糖在更大程度上直接结合到蛋白质表面。与蛋白质的比例增加，两种糖都表现出玻璃化转变温度升高，这使得蛋白质分子周围形成更完整的糖壳。最后，没有发现海藻糖和蔗糖结合时具有协同效应。总之，蛋白质稳定的精确机制可能会因温度而变化，这取决于蛋白质、糖和水之间的温度依赖性相互作用。这种可变性使得海藻糖在某些条件下成为一种优越的稳定剂，而在其他条件下则是蔗糖。
