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()*ecti'es+ Descri)e the chemical properties of enzymes

  e. "cti'e site, catalytic efficiency, specificity, cofactor,

  reulation, compartmentalisation.

+ Eplain the classification of enzymes

+ Descri)e the /inetics of enzyme catalysis

  -. ichaelis enten e0uation

  -. ine2ea'er Bur/ transformation

#eferences

  1. #ao, 3.. 4556. edical Biochemistry. 4nd Ed.

3e2 "e, Pu)lisher.

4. Baynes, 7.8. Dominicza/, .H. 4559. edicalBiochemistry. 4nd Ed. Else'ier os)y.

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8hat is Enzyme :+ Catalyst

+ %ncrease rate of chemical reactions 2ithout chanin the e0uili)rium

+ Enzymes different from other catalyst

  -. $pecific each enzyme eat different reaction

  -. ;reater catalytic po2er than other catalyst

  -. Catalytic action can )e reulated < to ensure rate

  of product formed not in ecess of amount needed

+ ocalization oran, tissue, cellular, su)cellular 

+ Holoenzyme = "poenzyme > Cofactor 

+ #eactant = $u)strate+ Classified in to 6 roups = type of reaction

 

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+ Enzymes are proteins lo)ular ?ri)ozyme is catalytic acti'e of #3"@

each 2ith a specific structure ?nati'e conformation@, function,

distri)ution of electrical chares, and surface eometry 2hose

specificity depends on their tertiary structure. Ahe tertiary structure

determines the three-dimensional shape. Ahey are each responsi)lefor control of a sinle reaction and are thus responsi)le for control of

meta)olism. 

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 "cti'e $ite

= three dimensional cleft created )y side chain of se'eral amino acid "mino acid from different reions in the linear se0uence of enzyme, folded,

side chains close at the acti'e side

 "mino acid is classified into 4 functional roups

1. Bindin residues

4. Catalytic residues

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- In an enzyme, a `binding site’ = an `active site’

- 4 types of binding of small molecule (red) to the binding site of

a protein (shaded)

Electrostatic Hydrophobic Hydrogen Bond Van Der Walls

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Enzyme $pecificity

+ 1. $u)strate

+ 4. #eaction

+ . ;roup

+ . ")solute roup

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Effect enzymes on acti'ation enery

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#eaction Profile 

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Eamples of

#eaction Profile 

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Eamples of

#eaction Profile

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Factors That Influence Reaction Rate

&nder a specific set of conditions, e'ery reaction has its o2n

characteristic rate, 2hich depends upon the chemical nature of 

the reactants.

Four factors can )e controlled durin the reaction

1. Concentration - molecules must collide to react

4. Physical state - molecules must mi to collide

. Aemperature - molecules must collide 2ith enouh enery to react

. Ahe use of a catalyst.

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Cascade Model : Type reaction of enzymes

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Effects of temperature

Each enzyme has an optimal temperature in 2hich it can function

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Effects of pH

Each enzyme has an optimal pH in 2hich it can function

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