BIOL 541 1st Edition Lecture 8 Outline of Last Lecture I. Molecular basis for properties. Outline of Current Lecture II.Competitive InhibitionIII. Non competitive InhibitionIV. CatalysisCurrent LectureBiochem Lecture 8: Competitive Inhibition:Lineweaver and Burk: Double reciprocal plot gives straight line graph to determine the parameters of kinetics.Competitive Inhibition: When inhibitor binds to the same binding catalytic site that the substrate binds but since it is not substrate, there is no reaction. In other words, it occupies the same place as the substrate and competes with the substrate for the active site.Non- Competitive Inhibition: When the inhibitor binds on the site of the enzyme separate from the catalytic site, so the substrate, enzyme, and inhibitor bind together with no competition.Catalysis:These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Enzymes need thermodynamic reactions. Spontaneous reactions enzymes need free energy to be reduced. In other words, the increase in the reactants free energy causes a decrease in the free energy of the product. A high energy state called the transition state is the hurdle, whereby small hurdle can be overcome and spontaneous reaction can go ahead. Free energy reactions can bounce this. Reactions that have high energy of activation have a difficult and slow reaction.Pyranose 6 member ring has 3 conformations: Boat, half chair and chair (less energy than boat). Half chair conformation has more energy than other forms. In other words, half chair can overcome hurdle.Enzymes can lower energy of activation by:1. Reactants in solution can form products. The enzyme thus has an active site for both substrate A and B and brings them together or APPROXIMATES reactants and causes randomness and enthropy. It brings proper joining of A and B to a molecule site oriented next to each other.2. Therefore, ORIENTATION mechanism affects free energy but not enthalpy.3. Sphere of hydration around A and B are displaced by enzymes as REARRANGEMENT of hydration spheres.4. Finally, enzymes do not bind perfectly to substrate. Therefore, not binding permanently but in transitional state causes DISTORTION of reactants and affects enthalpy (intrinsic energy in molecule). Conformation of the enzyme is bound half chair and allows lowering activation energy. Therefore, binding energy is for lowering activation energy.Thermodynamic and irreversible: That a specific reaction is irreversible depends upon coupling the reaction with downhill movement as a way of converting A to B. Glucose phosphate by phosphatase hydrolyses phosphate. This is a thermodynamically favorable reaction but free phosphate can not be added back to the glucose. The forward reaction has decrease in free energy than increase in free energy for the forward reaction. For glycolysis to be reversible, separate enzymes are needed.Kinetics of catalytic mechanism:Ordered or sequential mechanism: Enzyme binds both product and favors reaction directly between reactants.Ping Pong mechanism: Enzyme bounces between A and B. The enzyme accelerates the reaction and without permanently being altered. But can be transiently altered and needs to be regenerated. Transaminase transfers amino group from one amino acid to another but enzyme regeneration is