about enzymes

An enzyme is a catalyst that is utilized to quicken chemical reactions during the processes of metabolism. It has been demonstrated to raise people's quality of life. Enzymes are thought to raise living quality because they require less money to operate in the industries. One of the enzymes that will be highlighted in this experiment is amylase. The main species that will be affected by the temperature and time factors in the experiment are bacterial and fungal amylase. The experiment makes it very evident that temperature levels have a significant impact on the enzymes. Low temperatures make them slow, and vice versa. A rise in temperature increases the kinetic energy, hence, raising the probability for molecular collision. The graph is steeper for the former enzyme, hence, it is clear bacterial amylase degrades starch in vitro at a higher rate compared to fungal amylase

Objectives

The key objectives of the experiment include:

Determining the roles of enzymes

Analyzing temperature on the activity of enzymes

Enzymes are natal catalysts that are protein in nature. Their function is to primarily accelerate the chemical reactions in order for the metabolic processes to occur fast enough for life sustenance in the organism. As such, enzymes are significant propagators in biological reactions hence low concentration of some enzymes result in disorders.

The application of enzymes in industries has improved the quality of life due to the fewer funds investment in the production process. They are highly useful in leather and food processing companies in improving the quality of a product as well as in easing production process. In addition, less time is consumed and the raw materials are optimally used. Enzymes lower “activation energy of the reaction”, hence, raising the reaction rate. “Substrates bind the enzyme at the active site creating “enzyme- substrate complex”. Various “enzymes” work best under different conditions.” The enzyme to be emphasized on in this research practical is amylase. Two species of amylase are studied: fungal amylase and bacterial amylase. Amylases hydrolyze starch polysaccharide into its constituent monomers (Macgregor, Janecek &Svensso, 15), maltose or glucose which makes the enzyme useful in the brewing and baking industries.

Catabolism refers to chemical reactions that utilize complex molecules to produce energy. Smaller molecules are liberated in the process. Anabolic reactions consume energy while assembling small molecules to precipitate large and complex molecules. Starch catabolism involves the degradation of starch polymers into maltose units. Quantification of starch can be achieved using iodine test. Iodine solution is added to the test solutions, containing starch solution and amylase, at different times. The values are then plotted against time and compared to a standard curve.

Hypotheses

Fungal amylase

Ho- High temperature does not increase the rate of enzyme activity.

Ha- Amylase increases the rate of starch catabolism

High temperature beyond optimum denatures the enzyme slowing down reaction rates. . (Roy Daniel, Michael & Danson, 589).

Catalysis of starch proceeds at a slow rate. Incorporating amylase into the reaction speeds it up.

Bacterial amylase

Ho- low temperature does not reduce the rate of bacterial amylase activity

Ha- bacterial amylase increases the rate of starch catabolism

Low temperatures inactivate the enzymes since no respiratory reactions takes place in the cells. For this reason, no energy is available to set off the chemical reaction. Amylase enzyme reduces the activation energy required for starch catabolism, hence, increasing the reaction rate.

Table1.1: Hypotheses and inferences for fungal amylase

Temperature (o C)

Expected Results

Inferences

0

Blue-black color

Inactivated enzyme hence no conversion of starch to maltose

40

Muddy brown

Favorable temperature for amylase enzyme

Amylase converts starch to maltose

60

Yellow color

Optimum temperature for fungal amylase

The enzyme converts starch to maltose at its best

95

Light brown color

Temperature too high for the enzyme

The enzyme is denatured hence levels off the reaction rate.



Table1.2: Hypotheses and inferences for bacterial amylase

Temperature (0C)

Expected Results

Inferences

0

Blue-black color

Inactive enzyme

40

Muddy brown

Activated enzyme due to favorable temperature

60

Light brown color

Forward reaction at a reasonable rate. Optimum temperature not yet attained.

95

Light brown

Temperature beyond optimum. Enzyme denatured. No further reaction.



Procedure

Experimental Set up

A paper, labeled with temperatures and time on the side, was placed under the slot plates.

“A set of test tubes, four in number, were labeled with different temperature and enzyme source (B for bacterial amylase, F for fungal amylase).”

“Another set of four test tubes was labeled with a different temperature, enzyme source and the letter S for Starch solution”

“4 ml of 1 % starch solution was added to each of the test tubes labeled S.”

“Effect of Temperature on Amylase Activity”

“1ml of amylase enzyme was added to the first set of test tubes”. The mixture was subjected to differing levels of temperatures while adding iodine solution and starch respectively (Bernfeld, 150). The results were recorded as shown below;

Group results for bacterial amylase



Temperature (o C)

0

25

55

90

Time (sec)









0

5

5

5

3

2

5

5

4

2

4

5

5

4

2

6

5

5

4

2

8

5

5

4

2

10

5

5

4

2

















Graph 1: Bacterial amylase reaction on different temperature levels (group results)



Class mean results for the experiment

Temperature (o C)

0

25

55

90

Time( minutes)









0

5

5

4.67

5

2

5

4.83

4.33

3.17

4

5

4.83

3.67

2

6

5

4.83

3.5

2

8

5

5

3.5

1.83

10

5

5

1.83

1.83

















Graph 2: Bacterial amylase reaction on different temperature levels (Class results)





Results for fungal amylase

Group results

Temperature (o C)

0

25

55

90

Time( minutes)









0

5

5

5

5

2

5

5

4

5

4

5

5

4

5

6

5

5

4

4

8

5

5

4

4

10

5

5

4

4



Graph 3: Fungal amylase reaction on different temperature levels (group results)





Pictorial class results for bacterial amylase

Temperature (o C)

0

25

55

90

Time( minutes)









0

5

5

5

5

2

4.83

4.67

4

4.5

4

5

4.83

4.17

4.83

6

5

4.83

4

4.5

8

5

4.83

3.67

4.5

10

5

4.67

4

4.7















Graph 4: Fungal amylase reaction on different temperature levels (Class results)















Discussion

The independent variable is time and temperature the dependent variable. The two variables, that is time and temperature, are the control variables. The level of starch at 0 minutes is 100% since starch catabolism has not yet began. The dark blue color represents a high concentration of starch. Low temperature also lowers the reaction rate. (Roy M. Daniel, Michael J. Danson, 589). The optimum temperature for fungal amylase is 55 o C, and 70 o C- 90 o C for bacterial amylase.

Starch concentration is high at 0 minutes and maltose level at its lowest. As the experiment continues, the starch is degraded producing maltose. An increase in maltose concentration and a corresponding decrease in starch concentration result. The null hypothesis is rejected since a rise in temperature boosts the reaction rate up to a certain level when it levels off. Lower temperatures on the bacterial amylase part do lower the reaction rate by increasing the activation energy of the reaction. “At lower temperatures, the rate of enzyme activity is low since the kinetic energy of the molecules in the reaction is significantly low” (.Effect of temperature on enzyme kinetics, October 27). A rise in temperature increases the kinetic energy, hence, raising the probability for molecular collision. Temperatures beyond optimum result in conformational changes in the enzyme since the bonds and linkages are disrupted. Bacterial amylase degrades starch in vitro at a higher rate compare to fungal amylase. This is because the graph is steeper for the former enzyme.

Sources of Error

Contaminated reagents causes enzyme inhibition

Dirty apparatus give false implications

The tubes are allowed to stand for 5 minutes to allow for activation of the enzyme.

The 0 minute’s well is used to gauge the initial reaction rate prior to introduction of amylase enzyme.



Works Cited

A New Understanding of How Temperature Affects the Catalytic Activity of Enzymes. Trends

In Biochemical Sciences, Volume 35, Issue 10, October 2010, Pages 584-591, ISSN 0968-0004, 10.1016/j.tibs.2010.05.001.

Bernfeld, P. (1955). [17] Amylases, α and β. Methods in enzymology, 1, 149-158.

Brown D. E, Johnson F.H, &Marshland, The Luminescence, J cell and Contemporary

Physiology 20: 151, 2012

J. E. Nielsen and T. V. Borchert (2010) Protein engineering of bacterial alpha-amylases.

Biochimica et Biophysica Acta 1543, 253-274.

E. A. MacGregor, S. Janecek and B. Svensson (2011) Relationship of sequence and structure to

Specificity in the alpha-amylase family of enzymes. Biochimica et Biophysica Acta 1546, 1-20.

Kunitz, M.: The Kinetics and Thermodynamics of Reversible Denaturation of Crystalline

Soybean Amylase Inhibitor, J. Gen. Physiol. 32: 2, 2010

vlab.amrita.edu,. (2012). Effect of temperature on enzyme kinetics. Retrieved 27 October 2017,

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