Question

BIOCHEMISTRY

Propose a structure for a suicide inhibitor of the enzyme Enolase. Fully explain how and why the structure is likely to operate as asuicide inhibitor. (Think about what molecular characteristics are required for a suicide inhibitor). Draw a plot that illustrate the kinetics of the suicide inhibition and explain the curves/lines on the plot.

Answer 1

Suicide inhibition is a irreversible inhibition. Flouride is suicide inhibitor of the enzyme Enolase. It removes Mg⁺⁺/Mn⁺⁺ from the active site of enzyme. It is a mechanism based inactivation. The neuronal enolase structure is Mg2F2Pi complex (enolase fluoride/phosphate inhibitory complex, EFPIC). They are known as suicide inhibitor because it irreversibly inactivate the enzyme. It change the compound at its active site in to reactive compound.

8. Formation of phosphoenolpyruvate reversible O-P-O-CH CH2OH enolase CH 2-phosphoglycerate phosphoenolpyruvate enolase (inhibition by F-) Whem blood samples are taken for mesurement of glucose, it is collected in tubes containing fluoride 63

Irreversible inhibition is distinguished from noncompetitive inhibition by plotting V E Enzyme is inactivated until all of the irreversible inhibitor is used up EH