Reaction intermediates define the chemical steps of transformation from substrates to products, and capture of intermediates along catalytic pathways remains one focal point in the studies of enzymatic mechanisms. Performing enzymatic reactions in protein single crystals has been shown to be very effective in trapping and identifying unstable intermediates. In this critical review, we provide s...

Pulsed hydrogen exchange and other studies of the kinetic refolding pathways of several small proteins have established that folding intermediates with native-like secondary structures are well populated, but these studies have also shown that the folding kinetics are not well synchronized. Older studies of the kinetics of formation of the native protein, monitored by optical probes, indicate t...

Little is known about the induction period before the nucleation and growth of colloidal semiconductor quantum dots. Here, we introduce an approach that allows us to probe intermediates present in the induction period. We show that this induction period itself exhibits distinct stages with the evolution of the intermediates, first without and then with the formation of covalent bonds between me...

Protein unfolding intermediates are thought to play a critical role in conformational pathogenesis, acting as a 'gateway' to inactivation or pathogenic aggregation. Unfolding intermediates have long been studied either by populating partially-folded species at equilibrium using incresingly denaturing conditions, or by transiently populating 'kinetic' intermediates under fully denaturing conditi...

Six oxygen-associated vibrations were observed for reaction intermediates of bovine cytochrome c oxidase with 0, using time-resolved resonance Raman spectroscopy at room temperature. The isotope frequency shifts for 160180, have established that the primary iqtermediate is an end-on type dioxygen adduct of Fea3, which is followed by two oxoheme intermediates, and that the final intermediate app...

To determine whether channeling of glycolytic intermediates can occur in vascular smooth muscle (VSM), we permeabilized freshly isolated VSM cells from hog carotid arteries with dextran sulfate. The dextran sulfate-treated cells did not exclude trypan blue, a dye with molecular weight of ∼1,000. If glycolytic intermediates freely diffuse, plasmalemmal permeabilization would allow intermediates ...

To promote fidelity in nuclear pre-mRNA splicing, the spliceosome rejects and discards suboptimal substrates that have engaged the spliceosome. Whereas DExD/H box ATPases have been implicated in rejecting suboptimal substrates, the mechanism for discarding suboptimal substrates has remained obscure. Corroborating evidence that suboptimal, mutated lariat intermediates can be exported to the cyto...

this study presents a review on advanced oxidation processes (aop) for simultaneous removal of no and so2. aop is based on using a strong oxidant such as ozone and h2o2 which is able to generate highly reactive intermediates. the pollutant will be oxidized and removed by these intermediates. in recent years, aop has been considered as an effective and attractive technology in the field of flue ...