Diffusion-limited contact formation in unfolded cytochrome c: Estimating the max

2020-03-30 06:05:58

protein rate folding binding Of

责任者: Hagen, SJ;Hofrichter, J;Szabo, A;Eaton, WA 单位: NIDDKD,PHYS CHEM LAB,NIH,BETHESDA,MD 20892. 来源出处: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, v 93, OCT 15 1996, p 11615- 11617 摘要: How fast can a protein fold? The rate of polypeptide collapse to a compact state sets an upper limit to the rate of folding. Collapse may in turn be limited by the rate of intrachain diffusion. To address this question, we have determined the rate at which two regions of an unfolded protein are brought into contact by diffusion. Our nanosecond-resolved spectroscopy shows that under strongly denaturing conditions, regions of unfolded cytochrome c separated by similar to 50 residues diffuse together in 35-40 mu s. This result leads to an estimate of similar to (1 mu s)(-1) as the upper limit for the rate of protein folding. 关键词: laser photolysis; polymer dynamics; PANCREATIC TRYPSIN-INHIBITOR; COLLISION MODEL; BINDING DOMAIN; LIGAND-BINDING; KINETICS; COLLAPSE; MACROMOLECULES; MECHANISM; LIGAND-BINDING; KINETICS; COLLAPSE; MACROMOLECULES; MECHANISM; DYNAMICS; PATHWAYS DYNAMICS; PATHWAYS