CC2 LEC Enzyme Substrate PDF

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Summary

ENZYME SUBSTRATEFactors governing the rate of enzyme catalized1.) Substrate Concentration  Michaelis and Menten 1913  The substrate readily binds to free enzyme or a low substrate concentration.  With the amount of enzyme exceedingly the amount of substrate, the reaction rate steadily increases a...

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ENZYME SUBSTRATE Factors governing the rate of enzyme catalized 1.) Substrate Concentration  Michaelis and Menten 1913  The substrate readily binds to free enzyme or a low substrate concentration.  With the amount of enzyme exceedingly the amount of substrate, the reaction rate steadily increases as more substrate added

 Lineweaver Burk Equation -more accurate, sensitive and convenient to use. -double reciprocal of Michaelis-Menten

2.) Enzyme Concentration -if enzyme level is high, reaction is fast 3.) Temperature Temperature 25°C, 30°C, 37°C 37°C 40°C to 50°C 60°-65°C Low Temperature Every 10°C increase

EFFECT Optimum temp. Optimum temperature for enzyme reaction Denaturation (significant) Inactivation of the enzymes (no reaction) Enzymes are reversibly inactive Two-fold increase in enzyme activity

4.) pH -most reaction occurs at pH 7.0-8.0 (optimum pH)  Michaelis-Menten Kinetics -point of saturation V- (velocity) rate of enzyme activity Vmax- maximal rate of reaction when the enzyme is saturated  Enzyme Reaction -reaction rate is directly proportional to the substrate concentration.  Zero Order Kinetic -rate is independently -the velocity or the reaction is not affected by the addition of more substrate at a certain point -reaction depends only on enzyme concentration -when maximum velocity----------di ko po nasulat to huhu

5.) Salt and Protein Concentration - ionic state will increase the enzyme activity 6.) Cofactors -non-protein molecules Activators -inorganic cofactors -modify spatial configuration of the enzyme

Anticoagulants Anticoagulant Heparinized sample Citrate

Coenzyme -organic cofactors as secondary substrate Coenzymes must always be provided in excess.

EFFECT May inhibit amylase and AST Falsely lowers ----- and ALP

3 TYPES OF INHIBITOR a.) Competitive inhibitor (KABIT siya)  competes with substrate for binding to activate catalytic site  the inhibition is reversible because the substrate is more likely than the inhibitor to bind the active site and the enzyme has not been destroyed. b.) Noncompetitive inhibitor (Patagong KABIT)  bind to site on the enzyme which is different catalytic site  binds an enzyme at a place other than the active site and may be reversible in that some naturally present metabolic substances combine reversibly with certain enzymes. c.) Uncompetitive inhibitor (Nahuling may KABIT)  inhibition in which the inhibitor binds to the ES complex—increasing substrate concentration results in more ES complexes to which the inhibitor binds and, thereby, increases the inhibition.  The enzyme–substrate–inhibitor complex does not yield product. Assay of Enzyme -enzyme activity is reported in the IU (International Unit-Standard) -to standardized reporting of enzyme activity

-one IU is the amount of enzyme that catalyzes conversion of umol substrate to product per minute....