Application of 617-45-8, Enzymes are biological catalysts that produce large increases in reaction rates and tend to be specific for certain reactants and products. 617-45-8, Name is DL-Aspartic Acid, SMILES is NC(CC(O)=O)C(O)=O, belongs to amides-buliding-blocks compound. In a article, author is Ghorpade, Seema A., introduce new discover of the category.
The mechanism and high-free-energy transition state of lac repressor-lac operator interaction
Significant, otherwise-unavailable information about mechanisms and transition states (TS) of protein folding and binding is obtained from solute effects on rate constants. Here we characterize TS for lac repressor(R)-lac operator(O) binding by analyzing effects of RO-stabilizing and RO-destabilizing solutes on association (k(a)) and dissociation (k(d)) rate constants. RO-destabilizing solutes (urea, KCl) reduce k(a) comparably (urea) or more than (KCl) they increase k(d), demonstrating that they destabilize TS relative to reactants and RO, and that TS exhibits most of the Coulombic interactions between R and O. Strikingly, three solutes which stabilize RO by favoring burial/dehydration of amide oxygens and anionic phosphate oxygens all reduce k(d) without affecting k(a) significantly. The lack of stabilization of TS by these solutes indicates that O phosphates remain hydrated in TS and that TS preferentially buries aromatic carbons and amide nitrogens while leaving amide oxygens exposed. In our proposed mechanism, DNA binding-domains (DBD) of R insert in major grooves of O pre-TS, forming most Coulombic interactions of RO and burying aromatic carbons. Nucleation of hinge helices creates TS, burying sidechain amide nitrogens. Post-TS, hinge helices assemble and the DBD-hinge helix-O-DNA module docks on core repressor, partially dehydrating phosphate oxygens and tightening all interfaces to form RO.
Application of 617-45-8, Enzymes are biological catalysts that produce large increases in reaction rates and tend to be specific for certain reactants and products. I hope my blog about 617-45-8 is helpful to your research.