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: Enzymes

  1. #1

    Aug 2011
    -
    2,566

    Enzymes

    refresh
    refresh Enzymes




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    ( ) Enzyme ( in yeast ),

    .




    activiation Energy




















    .
    40000

    248000 4830000 .



    .



    .






    refresh







    pH .



    1/ :

    .
    2/ :



    , ,



    .




    Co-enzyme Co-factor

    + .

    .

    Substrate :
    Ý-
    ȝ-




    1

    ,





    The nature of enzyme action
    * Substrate



    .
    *







    ( )



    ( )

    ( ) .

    Energy of activation







    525 25560



    525 8700 .







    Specificity of enzymes
    *

    .
    *



    Stereo-chemical Specificity





    .

    Lactic dehydrogenase

    .
    * .

    Low Specificity

    .

    Lipase

    Peptidase Glucosidase
    *

    Group Specificity .
    * Absolute Specificity

    Kinase

    ATP



    Glucokinase ,

    ,



    ATP

    Relative Specificity .





    :

    : .

    : .





    .

    substrates



    Bindingsite.

    cofactor

    . .




    .






    .








    .





    :

    activators ( ) Coenzyme, prosthetic group .




    Enzyme example(s) with trivial name

    EC 1
    ( -)
    To catalyze / ; H O
    AH + B → A + BH (reduced)
    A + O → AO (oxidized)
    ,

    EC 2
    (
    another. The : - -
    AB + C → A + BC
    ,

    EC 3
    ( )

    AB + H2O → AOH + BH
    , ,

    EC 4

    ( : C-C, C-N, C-O or C-S
    RCOCOOH → RCOH + CO2


    EC 5
    ( )
    -, i.e.
    AB → BA
    ,

    EC 6
    ( )s
    C-O, C-S, C-N or C-C ATP
    X + Y+ ATP → XY + ADP + Pi


    Enzyme Kinetics
    : Enzyme Concentration


    in vito

    ,



    ,







    : Substrate Concentration






    ,







    : Temperature Effect


    50 5

    60 - 70 5

    () Coagulation



    .




    130

    .

    pH



    ,



    ,

    .








    ,

    .



    .




    2.5



    2527 5 60 5

    :
    Enzyme Stability

    -

    :

    Hydrogen ion concentration ( pH)
    .

    ,



    .




    pH 4-7 .

    : Activators and Inhibitors
    ʡ



    .
    ,







    ( CO )

    ( CN )

    .



    .




    ,

    :














    .

    :




    .











    .





    .

    :


    ase

    maltase
    ase

    dextrinase dextrin .
    :
    1-
    2-
    3-
    4-
    5-
    6-
    , : Digestive enzymes
    :

    - Hydrolases
    :

    pepain

    trypsin peptidases .






    Cellobiase - sucrase .

    Esterases

    Lipases

    - Phosphorylases




    Starch phosphorylase

    -1-



    : Digestive enzymes


    .


    Dehydrogenases




    reductant Hydrogen donator

    Oxidant Hydrogen acceptor



    1NAD 2 NADP

    Iron oxidases


    :

    1/ catalase



    .

    2/ peroxidas



    Copper oxidases
    :

    1/ Mono phenol oxidase .

    2/ Poly phenol oxidase





    .
    : Adding enzymes


    :
    /1 fumarase
    /2 aspartase

    : Transferring enzymes


    hexokinase

    ATP -
    : Isomerising enzymes


    /1 Phosphotriose isomerase
    - -

    /2 phosphoglucomutase

    -1- -

    : Linking enzymes




    ATP



    1/
    2/
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    ..

  2. #2

    Jul 2011
    712

    : Enzymes


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  3. #3
    Super Moderator
    Mar 2012
    11,190

    : Enzymes



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  4. #4

    Jul 2011
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    4,543

    : Enzymes




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    SARAH

  5. #5

    Jul 2011
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    : Enzymes



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