Demonstration by burst-phase analysis of a robust folding intermediate in the FF domain.
The role of intermediates in the folding reaction of single-domain proteins is a controversial issue. It was previously shown by different methods that an on-pathway intermediate is populated in the presence of sodium sulphate during the folding of the FF domain from HYPA/FBP11. Here we demonstrate using analysis of the amplitudes of kinetic traces that this burst-phase folding intermediate is present at different salt concentration and at various pH, and is also found in roughly 30 site-directed mutants. The intermediate appears robust to changing conditions and thus fulfils an important criterion for a productive molecular species on the folding reaction pathway.
Jemth
Per
P
MRC Centre for Protein Engineering, Hills Road, Cambridge CB2 2QH, UK.
Johnson
Christopher M
CM
Gianni
Stefano
S
Fersht
Alan R
AR
D019791:Guanidine / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D009154:Mutation; D011489:Protein Denaturation; D017510:Protein Folding; D020673:Protein Renaturation; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics; D014508:Urea / Q000494:pharmacology
D011506:Proteins; D014508:Urea; D019791:Guanidine