First order reaction protein folding

Small proteins can fold rapidly in a first-order reaction from a relatively expanded denatured state. 

Protein B from M. capsulatus (Bath) not only increases the product yields, but also influences the rate constant for the single turnover reaction of Hred with nitrobenzene (51,67). The pseudo-first-order rate constant increases up to 33-fold when Hred is titrated with protein B. Neither addition of reductase to Hox or Hred, nor addition of protein B and reductase to Hred, could similarly affect the rate constant. These... 

Series first-order processes are especially important in understanding metabolic pathway kinetics. Likewise, one should recognize that unassisted protein folding " is unlikely to be a single-step reaction (say U N), where U represents unfolded protein, and N is the native conformation. At a minimum, realistic schemes for protein folding are apt to occur as a series of isomerizations ... 

At present we are far from an understanding of the protein folding process. Even numerical methods as e.g. molecular dynamics simulations do not lead to realistic predictions. Experiments on the folding process have been performed initially on the millisecond time-scale. It was only recently that new techniques - temperature jump or triplet-triplet quenching experiments - allowed a first access to the nanosecond time domain [2-4]. However, the elementary reactions in protein folding occur on the femto- to picosecond time-scale (femtobiology). In order to allow experiments in this temporal range we developed a new... 

In Equation 10.8, AG is the folding free energy of the protein, is the first-order rate constant of the slow hydrogen exchange reaction at the C-2 position in the imidazole side chain of an unprotected histidine, m is 54G, / 5[denaturant], T is the temperature in Kelvin, R is the ideal gas constant, and [P] is the protein concentration expressed in n-ma- equivalents. Equation 10.8 can be daived from Equation 10.9, which is commonly used in the linear extrapolation method (LEM) to analyze denaturant-induced equilibrium unfolding curves [34] ... 

Protein folding studies generally concern liquid-phase phenomena however, HDX reactions can also be conducted in the gas phase (e.g., [84-90] for an overview see [91]). For instance, multiply charged ions of several model proteins reacted with DjO in a vacuum following pseudo-first-order kinetics [85]. It was also observed that removing solvent significantly increased conformational rigidity. In other work, ions of bovine ubiquitin were... 

Lipscomb et al detected three new intermediates in the catalytic cycle of sMMO isolated from M. trichosporium OB3b [61, 62] At 4 °C, the diferrous MMOH reacts with O2 in the presence of a 2-fold excess amount of protein B. The reaction has been followed by means of ESR and electronic absorption spectroscopies. The g = 16 ESR signal characteristic of the diferrous MMOH disappears at an apparent first order rate of 22 5 s" A new species having. ax and 430 nm (emax- 7500 M cm for each band) is generated with an average first order rate constant of 1 0.1 s" and then decayed at 0.05 0.01 s This intermediate was named compound Q. Since the formation rate constant of the compound Q is much similar than the apparent decay rate constant of diferrous state, the formation of another intermediate before the compound Q is assumed. 

Here, U, M, and M refer to unfolded, collapsed, and folded monomers, A to aggregates, and, k2 to the first- and second-order rate constants of folding and association, respectively. If the side reactions win, the protein will be degraded or precipitated, or chaperones will take care of Each step along the sequen-... 

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