BIOL 1300 Lecture Notes - Lecture 1: Tacrolimus, Quadratic Equation, Hyperbolic Function
Document Summary
Atom interactions: electrostatic, van der waals, covalent, ionic, hydrogen bonding, metal ion coordination. Reversible binding of a ligand and a protein. Dissociation constant: kd = 1/ka = [p][l]/[pl] (m) Low means that it binds tightly, in nm. Theta: fraction of occupied ligand-binding sites in a protein (0-1) Theta = occupied sites/total sites = [pl]/([pl]+[p]) = [l]/([l]+1/ka) Plot of theta vs. [l] is a hyperbolic function. When theta = 0. 5 --> [l] = 1/ka = kd. *kd is the molar concentration of **free** ligand at which half of the available ligand-binding sites are occupied. But, be careful about ratio of [l] and [p] Only applies when [l total] >> [p total] so that [l] ~ [l total] Binding equilibrium: can use quadratic equation to solve for [pl] Receptor for it is a cis-trans peptidyl-prolyl isomerase. Isomerase is the enzyme that catalyzes the conformational change between trans (90% of the time, more energetically favored) and cis.
