XRAY SCATTERING MEASUREMENTS OF RAPID CHAIN COLLAPSE DURING PROTEIN FOLDING

我们建议进行时间分辨SAXS测量的小 所有β折叠α淀粉酶蛋白，tendamistat。 中已知 光学动力学测量表明，这种蛋白质直接折叠到 在大约5毫秒的自然状态下， 折叠中间体。 我们计划测量 蛋白质的旋转展开的条件下， 折叠的速度可以减慢到50毫秒 通过增加最终变性剂浓度和/或通过 使用折叠速率降低的突变蛋白质。 这将 使我们能够验证一个假设， 必须发生在过渡状态到天然构象之前， 进入.

We propose to perform time-resolved SAXS measurements of the small all beta sheet alpha amylase protein, tendamistat. It is known from optical kinetic measurements that this protein folds directly to the native state in around 5 millisecs without going through a partially folded intermediate. We plan to measure changes of the radius of gyration of the protein unfolding under conditions where the rate constant for folding may be slowed down to a rate between 50 millisecs to 1 sec by increasing the final denaturant concentration and/or by using a mutant protein with a decreased folding rate. This will enable us to test the hypothesis that a non-specific polymer collapse must occur before the transition state to the native conformation is entered.