Perl D, Welker C, Schindler T, Schröder K, Marahiel M A, Jaenicke R, Schmid F X
Laboratorium für Biochemie, Universität Bayreuth, Germany.
Nat Struct Biol. 1998 Mar;5(3):229-35. doi: 10.1038/nsb0398-229.
The cold shock protein CspB from Bacillus subtilis is only marginally stable, but it folds extremely fast in a simple N reversible U two-state reaction. The corresponding cold shock proteins from the thermophile Bacillus caldolyticus and the hyperthermophile Thermotoga maritima show strongly increased conformational stabilities, but unchanged very fast two-state refolding kinetics. The absence of intermediates in the folding of B. subtilis CspB is thus not a corollary of its low stability. Rather, two-state folding and an unusually native-like activated state of folding seem to be inherent properties of these small all-beta proteins. There is no link between stability and folding rate, and numerous sequence positions exist which can be varied to modulate the stability without affecting the rate and mechanism of folding.
来自枯草芽孢杆菌的冷休克蛋白CspB稳定性极低，但它在简单的N可逆U两态反应中折叠速度极快。嗜热芽孢杆菌和嗜热栖热菌的相应冷休克蛋白构象稳定性显著增加，但两态快速重折叠动力学不变。因此，枯草芽孢杆菌CspB折叠过程中不存在中间体并非其低稳定性的必然结果。相反，两态折叠和异常类似天然态的折叠活化态似乎是这些小的全β蛋白的固有特性。稳定性和折叠速率之间没有关联，存在许多可改变的序列位置，在不影响折叠速率和机制的情况下调节稳定性。
