Different folding transition states may result in the same native structure

@article{Viguera1996DifferentFT,
  title={Different folding transition states may result in the same native structure},
  author={Ana Rosa Viguera and Luis Serrano and Matthias Wilmanns},
  journal={Nature Structural Biology},
  year={1996},
  volume={3},
  pages={874-880}
}
The crystal structures of two circular permutants of the α-spectrin SH3 domain with new termini within the RT loop (S19–P20s) and the distal loop (N47–D48s) have been determined at 2.02 and 1.77 Å resolution respectively. Both fold into the same three-dimensional structure as the wild-type SH3 domain except for the engineered loop that fuses the wild-type termini. The cleaved RT loop in S19–P20s loses nine conserved hydrogen bonds through local hydrogen bond unzipping; no hydrogen bond… 
The folding transition state between SH3 domains is conformationally restricted and evolutionarily conserved
TLDR
The protein engineering analysis of the α-spectrin SH3 domain at three different stability conditions reveals a folding transition state structured around the distal loop β-hairpin and the 310-helix, suggesting a transition state ensemble with little conformational variability.
Obligatory steps in protein folding and the conformational diversity of the transition state
TLDR
Analysis of the existence of obligatory steps in the folding reaction of the α-spectrin SH3 domain by mutating Asp 48 (D48G), which is at position i+3 of an isolated two-residue type II' β-turn, indicates that transition state ensembles in β-sheet proteins could be quite defined and conformationally restricted.
Loop length, intramolecular diffusion and protein folding
TLDR
The results suggest that transition state ensembles could be more homogenous then recently postulated and diffusion of different parts of the molecule relative to each other is taking place on going from the denatured ensemble to the transition state.
Role of native topology investigated by multiple unfolding simulations of four SH3 domains.
TLDR
Results indicate that, at least for small beta-sheet proteins, the folding mechanism is primarily defined by the native state topology, whilst specific interactions determine the statistically predominant folding route.
Dramatic stabilization of an SH3 domain by a single substitution: roles of the folded and unfolded states.
TLDR
Correlation of folding rates with AGADIR predictions of non- native helical structure in the diverging turn region, along with previous NMR evidence for non-native structure in this region of the unfolded state of the drkN SH3 domain, suggests that the free energy of the unfolding state also plays a role in stability.
Similarities between the spectrin SH3 domain denatured state and its folding transition state.
TLDR
It is proposed that the DSE of a protein will resemble the intermediate or transition state of its nearest rate-limiting step, as a consequence of simple energetic and kinetic principles.
Circularization changes the folding transition state of the src SH3 domain.
TLDR
The robustness of the src SH3-domain folding transition state to changes in topology is tested by covalently constraining regions of the protein with disulfide crosslinks and then performing kinetic analysis on point mutations in the context of these modified proteins.
Rational redesign of the folding pathway of a modular protein
TLDR
This work shows that this simple architecture makes it straightforward to direct the folding pathway of a repeat protein by design, and finds that folding of wild-type myotrophin is initiated at the C-terminal repeats.
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TLDR
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