Chapter 6 Slides (Part II) CH490

7/24/2019 Chapter 6 Slides (Part II) CH490

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Enzymes

Example Mechanism: Chymotrypsin

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Chymotrypsin Example

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972%$ :;

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Chymotrypsin Mechanism

=1$. :; =5>%1/21$ ?")6")#

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BK%*+/ >+>S$+ L"#$ %1 1R+ *%1%K&S* /C1+ 34+.


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=1$. ."1"#%1+/ 4+.."$-*+/ % /1."#N

#-*K+">RCK+

4+.


6/33


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=1$. G; H21$/ F0,$% I)

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=1$. J; H21$/ BC28D%

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10/33


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11/33

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Lysozyme Mechanism

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Lysozyme Mechanism

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19/33

Lysozyme Mechanism

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Enzymes

Transition State Analogs in Drug Design


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HIV Protease Transition State Analogs

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HIV Protease Transition State Analogs

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Enzymes

Kinetics


24/33

What is Enzyme Kinetics & Why Study It?

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How to Do Enzyme Kinetic Measurements

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How to Describe Enzyme Kinetics

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Ideal Rate:

Michaelis-Menten Equation

Deviations due to:

o Limitation of measurements

o

Substrate inhibition

o Substrate prep contains inhibitors

o Enzyme prep contains inhibitors

v =d[P]

dt=

Vmax

[S]

Km+[S]

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Enzymes

Michealis-Menten Kinetics


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Michaelis-Menten Plot

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VoDependence on Substrate Concentration [S]

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Vo=

Vmax

[S]

Km+[S]

Vo =

Vmax

[S]

Km

F# /"7 X6Y

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Vo =V

max

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The Lineweaver-Burk Plot

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Derivation of Enzyme Kinetics Equation

Start with a model mechanism

Identify constraints and assumptions

Carry out algebra ...

Simplest Model Mechanism: E + S!

ES!

E + Po One reactant, one product, no inhibitors

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Derivation of Enzyme Kinetics Equation

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Chapter 6 Slides (Part II) CH490

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