The Department of Chemistry and Biochemistry, The University of Texas as El Paso, El Paso, TX 79968, USA.
Molecules. 2020 Nov 16;25(22):5337. doi: 10.3390/molecules25225337.
Oxidative protein folding involves the formation of disulfide bonds and the regeneration of native structure (N) from the fully reduced and unfolded protein (R). Oxidative protein folding studies have provided a wealth of information on underlying physico-chemical reactions by which disulfide-bond-containing proteins acquire their catalytically active form. Initially, we review key events underlying oxidative protein folding using bovine pancreatic ribonuclease A (RNase A), bovine pancreatic trypsin inhibitor (BPTI) and hen-egg white lysozyme (HEWL) as model disulfide bond-containing folders and discuss consequential outcomes with regard to their folding trajectories. We re-examine the findings from the same studies to underscore the importance of forming native disulfide bonds and generating a "native-like" structure early on in the oxidative folding pathway. The impact of both these features on the regeneration landscape are highlighted by comparing ideal, albeit hypothetical, regeneration scenarios with those wherein a native-like structure is formed relatively "late" in the R→N trajectory. A special case where the desired characteristics of oxidative folding trajectories can, nevertheless, stall folding is also discussed. The importance of these data from oxidative protein folding studies is projected onto outcomes, including their impact on the regeneration rate, yield, misfolding, misfolded-flux trafficking from the endoplasmic reticulum (ER) to the cytoplasm, and the onset of neurodegenerative disorders.
氧化蛋白质折叠涉及二硫键的形成和从完全还原和展开的蛋白质(R)再生为天然结构(N)。氧化蛋白质折叠研究通过含有二硫键的蛋白质获得其催化活性形式的潜在物理化学反应提供了丰富的信息。最初,我们使用牛胰腺核糖核酸酶 A(RNase A)、牛胰腺胰蛋白酶抑制剂(BPTI)和鸡卵清溶菌酶(HEWL)作为模型含二硫键的折叠物,回顾了氧化蛋白质折叠的关键事件,并讨论了它们折叠轨迹的后果。我们重新检查了来自相同研究的发现,以强调在氧化折叠途径早期形成天然二硫键和产生“类似天然”结构的重要性。通过比较理想的(尽管是假设的)再生情景与在 R→N 轨迹中相对“晚期”形成类似天然结构的情景,突出了这两个特征对再生景观的影响。还讨论了一个特殊情况,即氧化折叠轨迹的所需特征仍然可以阻止折叠。这些来自氧化蛋白质折叠研究的数据的重要性被投射到结果上,包括它们对再生速率、产率、错误折叠、错误折叠通量从内质网(ER)到细胞质的运输以及神经退行性疾病的发生的影响。