Department of Biotechnology and Medical Engineering, National Institute of Technology Rourkela, Rourkela 769008, Odisha, India.
Department of Biotechnology and Medical Engineering, National Institute of Technology Rourkela, Rourkela 769008, Odisha, India.
Biophys Chem. 2023 Mar;294:106962. doi: 10.1016/j.bpc.2023.106962. Epub 2023 Jan 25.
Proteins can transform from their native state to a state having fibrillar aggregates characterized by cross β sheet structure. The fibrillar aggregates are known as amyloid and have been linked to several disorders. Disulfide bonds in proteins are one of the important factors that determine the propensity of aggregation. Hen Egg White Lysozyme (HEWL) was used by us as a model protein to decipher the role disulfide bonds play in the amyloid fibril formation and fibril morphology by using Dithiothreitol (DTT) as reducing agent at pH 2.7 and pH 7.4. We found that DTT can have different effects on HEWL amyloid depending on pH and the buffer used for preparing the amyloid fibrils. Our studies highlight the critical role of non-native disulfide bonds in amyloidogenesis and how disruption of these bonds can greatly affect the fibrillation process. Overall, these studies throw light on the fibrillation mechanism and can be explored further in designing effective inhibitors against amyloidosis.
蛋白质可以从其天然状态转变为具有纤维状聚集物的状态，这些聚集物的特征是具有交叉β片层结构。这些纤维状聚集物被称为淀粉样蛋白，与多种疾病有关。蛋白质中的二硫键是决定聚集倾向的重要因素之一。我们使用鸡卵清溶菌酶（HEWL）作为模型蛋白，通过在 pH 2.7 和 pH 7.4 下使用二硫苏糖醇（DTT）作为还原剂，来揭示二硫键在淀粉样纤维形成和纤维形态中的作用。我们发现，DTT 可以根据 pH 值和用于制备淀粉样纤维的缓冲液对 HEWL 淀粉样蛋白产生不同的影响。我们的研究强调了非天然二硫键在淀粉样蛋白形成中的关键作用，以及这些键的破坏如何极大地影响纤维形成过程。总的来说，这些研究阐明了纤维形成机制，并可以进一步探索设计针对淀粉样变性的有效抑制剂。
