Kuwajima K, Okayama N, Yamamoto K, Ishihara T, Sugai S
Department of Polymer Science, Faculty of Science, Hokkaido University, Japan.
FEBS Lett. 1991 Sep 23;290(1-2):135-8. doi: 10.1016/0014-5793(91)81243-2.
Kinetics of unfolding and refolding of a staphylococcal nuclease mutant, in which Pro117 is replaced by glycine, have been investigated by stopped-flow circular dichroism, and the results are compared with those for the wild-type protein. In contrast to the biphasic unfolding of the wild-type nuclease, the unfolding of the mutant is represented by a single-phase reaction, indicating that the biphasic unfolding for the wild-type protein is caused by cis-trans isomerization about the prolyl peptide bond in the native state. The proline mutation also simplifies the kinetic refolding. Importance of the results in elucidating the folding mechanism is discussed.
已通过停流圆二色性研究了一种葡萄球菌核酸酶突变体（其中Pro117被甘氨酸取代）的去折叠和重折叠动力学，并将结果与野生型蛋白的结果进行了比较。与野生型核酸酶的双相去折叠不同，该突变体的去折叠由单相反应表示，这表明野生型蛋白的双相去折叠是由天然状态下脯氨酰肽键的顺反异构化引起的。脯氨酸突变也简化了动力学重折叠。讨论了这些结果在阐明折叠机制方面的重要性。
