Alkyl Isocyanides Serve as Transition State Analogues for Ligand Entry and Exit in Myoglobin

Nucleophilicity parameters for alkyl and aryl isocyanides.

Glycosidase inhibitors as conformational transition state analogues.

A method for estimating the conformational similarity between hexopyranose rings is presented and used to probe the behaviour of various glycosyl hydrolase inhibitors as conformational transition state analogues.

Enzymatic transition states and transition state analogues.

Transition states are the balance point of catalysis. Bonds are partially made and/or broken at the transition state, and the energy of the extended system provides near-equal probability that the system forms products or reverts to reactants. Enzymatic catalytic sites provide dynamic electronic environments that increase the probability that the transition state will be formed. Alignment of re...

Mapping the pathways for O2 entry into and exit from myoglobin.

The effects of mutagenesis on geminate and bimolecular O2 rebinding to 90 mutants at 27 different positions were used to map pathways for ligand movement into and out of sperm whale myoglobin. By analogy to a baseball glove, the protein "catches" and then "holds" incoming ligand molecules long enough to allow bond formation with the iron atom. Opening of the glove occurs by outward movements of...

Transition State Analogues of Enzymatic Reaction as Potential Drugs

All chemical transformations pass through an unstable structure called the transition state, which is poised between the chemical structures of the substrates and products. The transi‐ tion states for chemical reactions are proposed to have lifetimes near 10-13 sec, the time for a single bond vibration. Thus, the transition state is the critical configuration of a reaction sys‐ tem situated at ...