Maity Haripada, Maity Mita, Krishna Mallela M G, Mayne Leland, Englander S Walter
Johnson Research Foundation, Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6059, USA.
Proc Natl Acad Sci U S A. 2005 Mar 29;102(13):4741-6. doi: 10.1073/pnas.0501043102. Epub 2005 Mar 17.
Equilibrium and kinetic hydrogen exchange experiments show that cytochrome c is composed of five foldon units that continually unfold and refold even under native conditions. Folding proceeds by the stepwise assembly of the foldon units rather than one amino acid at a time. The folding pathway is determined by a sequential stabilization process; previously formed foldons guide and stabilize subsequent foldons to progressively build the native protein. Four other proteins have been found to show similar behavior. These results support stepwise protein folding pathways through discrete intermediates.
平衡和动力学氢交换实验表明,细胞色素c由五个折叠子单元组成,即使在天然条件下,这些单元也会持续展开和重新折叠。折叠过程是通过折叠子单元的逐步组装进行的,而不是一次一个氨基酸地进行。折叠途径由一个连续的稳定过程决定;先前形成的折叠子引导并稳定后续的折叠子,以逐步构建天然蛋白质。已发现其他四种蛋白质也表现出类似行为。这些结果支持了通过离散中间体的逐步蛋白质折叠途径。