AC(Enzyme Kinetic) Rev

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    ENZYME KINETIC

    By: Luh Lian Pertiwi (0913031030)

    Chemistry Education Department, Faculty of Mathematics and Natural Sciences

    Ganesha Education University

    Abstract

    The enzyme is a biocatalyst that can increase the speed of reactions in biological systems and

    enzymes affect reaction rates when equilibrium is reached, but did not affect the total

    equilibrium of the reaction. Enzymes assist the reaction by providing a reaction pathway that

    has a low activation energy for the substrate into a product transition. Reaction rate of the

    reaction catalyzed by the enzyme increases with the addition of substrate concentration, until

    reaching a state with the addition of the substrate concentration does not affect the initial

    reaction rate. This situation is referred to as the maximum reaction rate (Vmax). The aim of this

    experiment is to determine Vmax and KM for enzymetic rate reaction and substrat concentration.

    According to graph of relationship 1/Vo to 1/[S], it can be determined Vmax and KM value.According to the experiment, KM value and VMax value of enzymetic rate recation of tripsin with

    kasein is 8,84 mg/mL and 1,938 mol/menit.

    Keyword : enzyme, Vmax and KM.

    Introduction

    In the reaction, enzyme can react with the reactants and also can be recovered at the time

    of formation of the product. The phenomenon is what causes the enzyme can be regarded as a

    catalyst. Enzymes are the catalysts of biochemical reactions that play a role in the specific

    enzyme is often referred to as a biocatalyst. As a biocatalyst, the enzyme can increase the speed

    of reactions in biological systems and the enzyme itself does not change during the reaction. Inaddition, the enzyme also affects the reaction rate when equilibrium is reached, but did not affect

    the total equilibrium of the reaction. Enzymes assist the reaction by providing a reaction pathway

    that has low activation energy for the transition into a product compared to the substrate without

    the catalysis process. The catalytic activity of the enzyme is very sensitive to conditions such as

    temperature, pH, and the strength of the product. Enzyme reaction kinetics assumes that a

    complex between the enzyme and the substrate is formed immediately and reversibly. This

    complex then breaks down slowly and produces enzymes.

    The speed of biochemical reactions that are catalyzed by an enzyme commonly used as

    the value at time zero (Vo symbol, within minutes mol-1), because the highest velocity occurs in a

    state where the reaction product has not been established. In these circumstances, the greatest

    concentration of substrate and enzyme is not inhibited by its product feedback. Plot of the

    reaction products formed with time on the enzymatic reaction showed that the initial stage occurs

    a linear graph, and then followed by a decrease in reaction rate because most of the substrate has

    been used in the reaction or the enzyme activity decreased. Initial reaction velocity (Vo) is

    obtained by drawing a straight line through the linear curve at zero time point and the slope of a

    straight line equal to Vo.

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    Reaction rate depends on the concentration of enzyme that acts as a catalyst in a reaction.

    At low substrate concentration, if the substrate concentration is increased two times, then the

    initial reaction velocity (Vo) has doubled. This means that at low substrate concentration of

    enzymatic reaction rates of order one. However, at high concentrations, increasing the substrate

    concentration will lead to changes in Vo is very small and at very high substrate concentrations,

    increasing the substrate concentration will not affect the price of V o (Vo constant prices). This

    situation is caused because the enzyme was saturated by the substrate, or in other words the

    entire active enzyme has a substrate binding.

    The reaction rate increases as substrate concentration increased up to a point where said

    enzyme is saturated with substrate. The measured initial velocity reaches a maximum speed and

    is not affected by the subsequent increase in substrate concentration, because the substrate is in

    molar excess. Overall reaction rate depends on the speed of product dissociation from the

    enzyme, and the addition of the substrate will not affect Vo. Plot Vo against [S]-shaped

    hyperbolic.

    (a) (b)

    (b)Figure 1 (a). The relation concentration of substrate and Vo plot

    (b). The relation of 1/Vo and 1/[S] plot Lineweaver Burk

    Michaelis and his friends claimed that the enzymatic reaction at various concentrations of

    substrates having two phases, namely: (1) when a low substrate concentration ([S]) is low, then

    not all of the active enzyme bound to the substrate and (2) if molecule of the substrate increases,

    the active side was entirely bound to the substrate. At this time the enzyme has been working

    complete. From the capacity Michaelis and friends statement can also be proven by metematics.

    The curve in Figure 1 (a) Michaelis-Menten equation satisfies is follows:

    [S]K

    [S]VV

    M

    maks

    o+

    =

    Where : Vo = the velocity of enzyme by the concentration of substrate [S]

    KM = Michaelis Menten constant (mol perliter)

    Vmaks = Maximum velocity

    From the equation above its can be:

    Kinetic Zero-order (Fase II)

    Mixture kinetic zero and

    first-order

    KineticFirst-order(Fase I)

    Maximum Velocity (V)

    V0

    Vmaks

    Vmaks

    KM

    [S]

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    E + Sk1

    k2

    k3k4

    ES E + P

    The specificity of an enzyme catalyzed by the enzyme appears to the formation of the

    enzyme substrate complex (ES), which then decomposes into enzyme and products (E and P). In

    this case k1, k2, k3, and K4 is the reaction rate constants. Initially be achieved disintegration of thestate of the enzyme rate equal to the speed of formation of ES.

    k1[S][E] + k4 [E][P] = k2 [ES] + k3 [ES]

    32

    4

    32

    1

    kk

    [P]k

    kk

    [S]k

    [E]

    [ES]

    +

    +

    +

    =

    In the condition of concentration is P (product) is very small so the constant of k1, k2, k3

    and k4 can be written is as follows:

    KM =1

    32

    k

    kk +.

    The equation is:

    [S]

    K

    [ES]

    [E] M=

    If the amount of total concentration of enzyme [E]t and [ES] so the concentration [E] =

    [E]t [ES], as follows:

    [S]

    K1

    [ES]

    [E]

    [ES]

    [ES][E]

    [ES]

    [E] Mtt==

    =

    1[S]

    K

    [ES]

    [E] Mt+=

    Maximum celocity (V if maks) if the enzyme the shape is complete if all of enzyme in

    complex form with the substrate. But Vo directly proportional with [ES]. Its can be written is as

    follows:

    1[S]

    K

    V

    VsO

    [ES]

    [E]

    V

    V Mmakstmaks+==

    In the figure 1 (a) can be seen that KM as mole perliter. And KM is higher so can be written

    is as follows:

    M

    maks

    K

    [S]VV=

    In this case V depends on the substrate concentration (filtrate reaction order) and in

    Figure 1 (a) can also be seen kinetic and first-order zero. Thus, the Michaelis-Menten equation iseligible for a simple reaction that is catalyzed by the enzyme. KM is often defined as the

    dissociation constant of the reaction catalyzed by the enzyme. In the simple reaction can be seen:

    E + Sk1

    k2ES maka K s=

    [E][S]

    [ES]=

    k2k1

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    Because KM is1

    32

    k

    kk +so Ks =

    1

    32

    k

    kk +

    So, KM will always same or bigger than Ks. can be seen from the equation:

    maksmaks

    M

    M

    maks

    V

    1

    [S]

    1

    V

    K

    V

    1So

    [S]K

    [S]VV +

    =

    +

    =

    The equation above is identical with line equation is y = ax + b, where:

    y =maksmaks

    M

    V

    1bdan

    V

    Ka;

    [S]

    1x;

    V

    1===

    The equation can be formulated by Lineweaver-Burk and like figure 1 (b). Based in the

    figure 1 (b), line equation with the gradient inoV

    1is

    maksV

    1, in

    [S]

    1is

    MK

    1 . The plot of

    line ismaks

    M

    V

    K. Plot Lineweaver-Burk can be used to determine inhibition that occurs in the

    enzymatic reaction.

    Spectrophotometer

    Spectrophotometer is the method that used to qualitative and quantitative analysis in

    solution. Spectroscopy imply the measurements how far the light energy absorption as a function

    of the wavelength of radiation. Instruments that used in this method its called by

    spectrophotometer. In analyzing the uses of UV-Vis spectrophotometer should note the

    following:

    a. Formation of colored compounds

    This step is conducted if the analyzed compounds not absorbing visible region. In thiscase the compound must be converted into other compounds that can do the absorption or

    reacted with a reagent that form color so can absorb visible light. Reagents that cause

    color, must meet several requirements such as: reaction with a substance that is analyzed

    to be selective and sensitive, do not form colored compounds with other substances that

    exist in solution, they react with other substances which must be analyzed quickly and

    quantitatively (perfect), color or compounds that are formed must be sufficiently stable

    for a specified period, and not too fast changes with changes in pH.

    b. Selection of wavelength

    Wavelengths required in a quantitative analysis by spectrophotometry is the wavelengthcorresponding to maximum absorbance (peak absorption). This is caused by changes in

    absorbance for each unit of concentration is greatest at the maximum wavelength, it will

    obtain the maximum sensitivity as well. Wavelengths required in a quantitative analysis

    by spectrophotometry.

    Description:

    Violet : 400 - 420 nm

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    Indigo : 420 - 440 nm

    Blue : 440 - 490 nm

    Green : 490 - 570 nm

    Yellow : 570 - 585 nm

    Orange : 585 - 620 nm

    Red : 680 780 nm

    c. Preparation of calibration curve

    For calibration curves, created a standard solution with various concentrations of the

    unknown. Absorbance of standard solution is measured, and then plots the absorbance

    (A) against concentration (C), the curve formed is called the calibration curve.

    In the analysis using UV-Vis spectroscopy is used the basic law of Lambert-Beer.

    Lambert-Beer law states the relationship between the intensity of light absorbed by the

    concentration and the thick solution through which the beam. If a beam of light with a

    certain length is passed in a solution containing absorbent material, some light will be

    absorbed and some light transmitted. Simply, Lambert-Beer law can be shown in thefollowing scheme.

    Light or radiation with the intensity Po of that passes through a medium-thick b

    containing a solution with concentration C, will result in reduced intensity of P so that P

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    Information obtained from ultraviolet and visible spectra:

    1. The maximum wave length ( maks )

    Quantitative analyse, for all the measure based on analisis kuatitatif, maks , but forthe compound that already know frequently used approach Woodward-Fieser.

    Qualitative analyses : less informatif.

    2. Absorptivity maximum of molar( maks ); qualitative analyses is the information transisi

    electronic.

    Lambert-Beer Laws

    If a beam of light with specific wavelength is passed in a solution containing absorbent

    material, then some light will be absorbed and some will be forwarded. The relationship between

    the intensity of light absorbed by the concentration and the thick solution through which thebeam expressed by Lambert-Beer equation as follows.

    A = -log I / Io = bC

    (Muderawan,2009)

    Where, A = absorbance

    I = Intensity of light emitted by the solution in the cell

    Io = intensity of light emitted by the solvent in the same cell at I

    = coefficient of extinct species absorbent or constant comparison.

    b = Length of solution through which the light (typically 1 cm)

    C = Concentration of absorbing species in units of mol L-1 (M)

    Slope = b

    The relation between concentration

    and absorbance

    The relation between

    concentrations with transmittance

    C

    (mg/

    L)

    T

    Lambert-Beer diagram

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    (Ismono,1978)

    The greater the intensity of light is absorbed then the value of A will become bigger and

    the intensity of the transmitted beam will be smaller. Often times in real terms in the

    measurement result, polt. Beer law is not linear throughout the entire concentration observed.

    Curvature states that is not a constant, which depends on the concentration. value is expected

    to depend on the nature absorbance agent species in solution and at a wavelength of radiation. In

    practice the deviation is usually caused by the deviation on the basis of chemical and diversion of

    the instruments used.

    Materials and Method

    In this experiment about the determine the protein content of the egg whites in the

    sample solution through the use of methods of Lowry at Thursday 13 April, 2012. This

    experiment conducted in Organic Laboratory Undiksha.

    Materials and equipment

    The materials that used in this experiment are casein solution, Folin-Ciocalteu reagent,

    aquades, trypsine solution, NaOH solution, and TCA solution and the equipment that used are

    test tube, volumetric pipette, volumetric flask, drop pipette, graduated cylinder glass and beaker

    glass.

    Procedure

    Prepare 10 test tubes. In each of test tube added by casein, buffer and trypsin in different

    concentration like is as follows:

    No Test tube Casein (mL) Buffer phosphate

    (mL)

    Trypsin (mL)

    It= 0 minute 0,1 5,9 1

    t = 20 minute 0,1 5,9 1

    IIt= 0 minute 0,5 5,5 1

    t = 20 minute 0,5 5,5 1

    IIIt= 0 minute 1,0 5,0 1

    t = 20 minute 1,0 5,0 1

    IVt= 0 minute 3,0 3,0 1

    t = 20 minute 3,0 3,0 1

    V t= 0 minute 5,0 1,0 1

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    t = 20 minute 5,0 1,0 1

    At the incubation 20 minutes

    1. In each test tube that contain casein incube 5 minute in water incubator 35oC. stirrer and

    add buffer phosphate solution pH 8,0 and trypsin solution (based on the table).

    2. The solution 20 minutes in water incubator35oC after added trypsin.

    3. After incubation 20 minutes add 3 mL of TCA 20% solution into each of test tube. Than

    cooled in 30 minute in ice batch to get the precipitate perfect.

    4. After that filter the solution by Anson method. 2 mL of filtrate add by 4 mL NaOH 0,5

    M, then add the reagent Folin-Ciocalteu wait 10 minute. Measure the absorbance by

    spektronik 20+.

    At the incubation 0 minute

    1. In each test tube add buffer fosfat solution and trypsin. Than add the TCA solution 20%

    incube 5 minute in water incubator 35oC.

    2. In each test tube added by casein solution ditambahkan larutan kasein. Than cooled in 30

    minute in ice batch to get the precipitate perfect.

    3. After that filter the solution by Anson method. 2 mL of filtrate add by 4 mL NaOH 0,5

    M, then add the reagent folin ciocalteu wait 10 minute. Measure the absorbance by

    spektronik 20+.

    Result and Discussion

    In this experiment tests performed is the enzyme kinetics reaction, where the value of

    these tests can be determined Vmax and KM (Michaelis-Menten constant) over the curve of therelationship between the reaction rate and substrate concentration.

    In this experiment used as the substrate is a casein solution, while being used as the

    enzyme is trypsin solution. Trypsin is a proteolytic enzyme, this enzyme catalyzes the hydrolysis

    of the peptides bond, where in the peptide bonds were broken in the substrate casein is located on

    the carboxyl side of lysine or arginine residues are charged.

    N C

    H

    H

    C

    R1

    O

    N

    H

    C

    H

    R2

    C

    O

    + H2O N

    H

    C C

    R1

    O

    O-

    H

    ++H3N C C

    H

    R2

    O

    Peptides Carboxcyl Amine

    There are two treatments (time) is done in this experiment the incubation time of 0

    minutes and 20 minutes. In this experiment provided 10 tubes, for an incubation time of 0

    minutes, while the tubes for 20 min incubation. In this case also do a variation of the

    concentration of substrate in each tube. For the incubation of 20 minute, casein solution is

    incubation first

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    Incubation of casein in 5 minute

    This treatment of substrate conditions at maximum temperature is 35oC. Into the casein

    solution that incube add the buffer fosfat solution (pH 8,0) so the volume become 6 mL in each

    test tube. The objective of dilution is to make the substrate condition in each test tube are

    different so the plot of reaction rate is different. Then the solution is added by trypsine solution

    1 mL in each test tube. The addition of trypsin solution aims to catalyze the hydrolysis reaction

    under on the peptide bonds in casein. Peptide bonds were broken by trypsin is the bond that lies

    at the carboxyl side of lysine and arginine residues.

    Incubation at 20 minute

    After the incubation the solution is added by TCA ( tri chloro acetat). The aim of this

    solution is to stop the trypsine enzyme so can be analysis the effect of substrate concentration

    in enzyme of reaction rate. The addition of TCA 20% solution that caused the precipitate form

    in the test tube after cooled 30 minute.

    Brown precipitate which formed a precipitate of casein protein and the enzyme trypsin. The

    addition of a solution of TCA was able to stop the activity of the enzyme and substrate solution

    of casein given TCA solution is acidic, so the addition of either TCA can cause denaturation of

    the enzyme and the casein. Structures that cause clotting TCA are as follows.

    C CCl

    Cl

    Cl

    O

    OH

    Structure of TCA

    With the addition of acid to the solution, causing denaturation protein both the substrate and the

    enzyme trypsin. Also, the addition of TCA solution causes the pH of the acidic solution to be

    down (acid) so that the substrate complex formed is unstable and the activity of the enzyme to

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    catalyze the hydrolysis of casein in a standstill due to changes in pH. This is because the enzyme

    trypsin to work at optimum pH is pH 8.0.

    After filtering the precipitate, the resulting filtrate treated with the method of Anson,

    where the filtrate to each tube to 2 mL after adding 4 ml of 0.5 M NaOH was added Folin-

    Ciocalteu reagent. Folin-Ciocalteu reagent is a mixture between fosfotungstat and fosfomolibat

    in yellow. These reagents can be reduced by the phenolic group on the amino acid tyrosine in

    the filtrate contained tungstate and molybdenum producing blue-green. Based on the results of

    the experiment, when the filtrate was added Folin-Ciocalteu reagent green in solution. The

    resulting solution is then measured by using UV vis 20+.

    For the 0-minute incubation time, the order is different from the incubation of 20

    minutes, which at time 0 minute incubation in a row was added phosphate buffer, trypsin

    solution, a solution of TCA to each tube. After incubation for 30 minutes then added a solution

    of casein at varying volume for each test tube. Calculation of substrate concentration for each

    tube as follows.

    The filtrate obtained is done by Anson, where the filtrate to each tube to 2 mL after

    adding 4 ml of 0.5 M NaOH was added Folin-Ciocalteu reagent. Folin-Ciocalteu reagent is a

    mixture between fosfotungstat and fosfomolibat in yellow. These reagents can be reduced by the

    phenolic group on the amino acid tyrosine in the filtrate contained tungstate and molybdenum

    producing blue-green. Based on the results of the experiment, when the filtrate was added Folin-

    Ciocalteu reagent the color is green. The resulting solution is then measured using a

    spectrophotometer at a wavelength of 700 nm. Based on the experiments conducted, the

    following is a comparison of observations absorbance for tube t = 0 and t = 20.

    Table. Observation result of absorbance

    No Test tube Absorbance Transmitant (%)

    I t = 0 minute 0.096 81t = 20 minute 0.139 85

    IIt = 0 minute 0.184 92

    t = 20 minute 0.187 83

    IIIt = 0 minute 0.211 72

    t = 20 minute 0.229 89

    IVt = 0 minute 0.259 75

    t = 20 minute 0.387 88

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    To calculate and determine the value of KM and VMax, so be must determine the value of

    [S] and [Vo]. The value [S] concentration of casein in the test tube is different value. The

    calculation is as follows:

    Massa of casein that added is 5 gram in 250 mL aquades.

    [casein] = mL500

    gram5

    = 10 mg/mL

    Test tube 1

    V1 = 0,1 mL; V2 = 6 mL; M1 = 10

    mg/mL

    M2=

    mg/mL6

    1

    mL6

    mg/mL10xmL0,1=

    [S] = mg/mL6

    1

    6.mL/mg[S]

    1=

    Test tube 4

    V1 = 3,0 mL; V2 = 6 mL; M1 = 10

    mg/mL

    M2 =

    mg/mL5mL6

    mg/mL10xmL3,0=

    [S] = mg/mL5

    mL/mg2.0[S]

    1=

    Test tube 2

    V1 = 0,5 mL; V2 = 6 mL; M1 = 10

    mg/mL

    M2 =

    mg/mL6

    5

    mL6

    mg/mL10xmL0,5=

    [S] = mg/mL6

    5

    mL/mg1.2[S]1 =

    Test tube 3

    V1 = 1,0 mL; V2 = 6 mL; M1 = 10

    mg/mL

    M2 =

    mg/mL3

    5

    mL6

    mg/mL10xmL1,0=

    [S] = mg/mL3

    5

    mL/mg0.6[S]1 =

    For the calculation of Vo can be determine the value of absorbance by spectrophotometer

    dapat ditentukan dengan besaran absorbansi ketika diukur dengan spektronik 20+. The absorbance

    is as follows:

    A = .b.C

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    Because .b is constant, so can assume that .b is constants. So, A = k x C, where A =

    absorbance C = concentration k = constants. Based on the equation so AC

    So the equation of velocity iso

    ot

    [C]V =

    ot

    AV =

    oV

    1

    A

    1=

    The calculation of absorbance can be calculating the absorbance in t=20 and t=0 so theabsorbance:

    Incubation time o minute Incubation time 20 minute

    Test tube I

    %T = 81; T = 0.81

    A = -log T = -log 0.81 = 0.096

    1/A = 1/0.096 = 10.41

    1/V0 = 10.41

    Test tube II

    %T = 92; T = 0.92

    A = -log T = -log 0.92 = 0.184

    1/A = 1/0.184= 5.43

    1/V0 = 5.43

    Test tube III

    %T = 72; T = 0.72

    A = -log T = -log 0.72= 0.211

    1/A = 1/0.211= 4.73

    1/V0 = 4.73

    Test tube IV

    %T = 75; T = 0.75

    A = -log T = -log 0.75=0.259

    1/A = 1/0.259= 3.86

    1/V0 = 3.86

    Test tube I

    %T = 85; T = 0.85

    A = -log T = -log 0.85 = 0.139

    1/A = 1/0.139 = 7.19

    1/V0 = 7.19

    Test tube II

    %T = 83; T = 0.83

    A = -log T = -log 0.83 = 0.187

    1/A = 1/0.187= 5.34

    1/V0 = 5.34

    Test tube III

    %T = 89; T = 0.89

    A = -log T = -log 0.89= 0.229

    1/A = 1/0.229= 4.36

    1/V0 = 4.36

    Test tube IV

    %T = 88; T = 0.88

    A = -log T = -log 0.88= 0.387

    1/A = 1/0.387 = 2.58

    1/V0 = = 2.58

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    Based the calculation the table is as follows:

    Tabel 2. Calculation table of 1/A

    No Test tube %T T A 1/A

    It = 20 minute 81 0.81 0.096 10.41

    t = 0 minute 85 0.85 0.139 7.19

    IIt = 20 minute 92 0.92 0.184 5.43

    t = 0 minute 83 0.83 0.187 5.34

    IIIt = 20 minute 72 0.72 0.211 4.73

    t = 0 minute 89 0.89 0.229 4.36

    IVt = 20 minute 75 0.75 0.259 3.86

    t = 0 minute 88 0.88 0.387 2.58

    Based on the table can make curve of the relation between 1/V 0 versus 1/[S] at the time of

    incubation 0 minute and 20 minute.

    The curve of the relation between 1/V0 versus 1/[S] at the incubation time o minute is as

    follows:

    Test Tube 1/V0 1/[S] (mL/mg )

    1 10.41 6

    2 5.43 1.2

    3 4.73 0.6

    4 3.86 0.2

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    From the curve we y get the line equation is 1.086x + 3.934The relation with the Lineweaver-Burk can be calculate by 1/Vmax, 1/[S] and -1/KM. Lineweaver-

    Burk equation:

    maksmaks

    M

    oV

    1

    [S]

    1

    V

    K

    V

    1+

    =

    From the equation, the value ofmaksV

    1when the x = 0, so

    y = 1.086x + 3.934

    y = 1.086 0 + 3.934

    y = 3.934so that,

    maksV

    1= 3.934

    Vmaks = utemol min/25.03.934

    1=

    So when the[S]

    1is -

    MK

    1, its same with y = 0, so

    y = 1.086x + 3.934

    0 = 1.086x + 3.934

    1.086x = -3.934

    x = -3.62

    its means the -MK

    1= -3.62

    KM =3.62

    1= 0.276 mg/mL

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    The curve of the relation between 1/V0 versus 1/[S] at the incubation time 20 minute is as

    follows:

    Test Tube 1/V0 1/[S] (mL/mg )

    1 7.19 6

    2 5.34 1.2

    3 4.36 0.6

    4 2.58 0.2

    From the curve we get the line equation is 0.629x+ 3.609

    The relation with the Lineweaver-Burk can be calculate by 1/Vmax, 1/[S] and -1/KM. Lineweaver-

    Burk equation:

    maksmaks

    M

    oV

    1

    [S]

    1

    V

    K

    V

    1+

    =

    From the equation, the value ofmaksV

    1when the x = 0, so

    y = 0.629x+ 3.609y = 0.629 0+ 3.609

    y = 3.609

    so that,

    maksV

    1= 3.609

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    Vmaks = utemol min/277.03.609

    1=

    So when the[S]

    1is -

    MK

    1, its same with y = 0, so

    y = 0.629x+ 3.609

    0 = 0.629x+ 3.609

    0.629x = -3.609

    x = -5.73

    its means the -MK

    1= -5.73

    KM =5.73

    1= 0.174mg/mL

    The value of KM at the incubation 20 minutes is 0.174 mg/mL and the incubation time at 0

    minute is 0.276 mg/mL. From the experiment data the value of KM at the incubation 20 minutelower than the incubation in 0 minute. The value of KM show the stability complex of enzyme

    and the substrate where the value of KM is higer its mean the bond of enzyme and substrate is

    less. From the value of KM can be concluded that if the time is increase so the complex enzyme

    and substrate will stable because the bond of the enzyme and substrate is strong.

    Conclusion

    Based on the data result and data analyze that we have been done, so can be concluded

    the value of KM from the experiment that have been done is 0.174 mg/mL in 20 minute and at 0

    minute the value of KM is 0.276 mg/mL.

    Acknowledgment

    Thanks to the god almighty who has bless me to finishing this article with the title Enzyme

    Kinetic. This article is made for me assignment in Biochemistry Practice lesson. In process to

    create this paper, the author found some problem. It because of my knowledge still need to

    improvement. But because of the guidance and big support from many peoples, so I can finish it.

    Therefore, the authors want to say thanks to the:

    1. Mr. Dr. I Nyoman Tika, M.Si. as my lecturer who has guide me,

    2. Mrs. Dra. Siti Maryam, M.Kes. as my lecturer who has guide me,

    3. My best friend in RKBI Class who has supported me, and

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    4. Many other peoples who has supported me.

    This article is still need improvement and still contains many of mistakes, because of that

    authors need advice and critics to make this article will better and can useful for many people.

    Thank you.

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    Indonesia

    Redhana, I Wayan dan Siti Maryam. 2003.Penuntun Praktikum Biokimia. Singaraja : IKIP

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    Tika, I Nyoman. 2007.Penuntun Praktikum Biokimia. Singaraja: Universitas Pendidikan

    Ganesha

    Wirahadikusuma, Muhamad. 2001.Biokimia :Protein, Enzim, dan Asam Nukleat. Bandung :

    Penerbit ITB

    Muderawan, I Wayan. 2009.Analisis Instrumen. Singaraja : Undiksha Press