Detailed Analysis of Enzyme Structure, Function, and External Factors

This report provides a comprehensive overview of enzyme structure and its direct relationship to function. It explores the primary, secondary, and tertiary structures of enzymes, emphasizing how these structural features enable catalytic activity. The report delves into the concepts of activation energy, the lock and key and induced fit models of enzyme action. Furthermore, it discusses the impact of external factors such as temperature, pH, and substrate concentration on enzyme activity, detailing how these factors can influence reaction rates. The analysis includes relevant references, and provides a solid foundation for understanding enzyme behavior in biological systems.

HEALTH PROFESSIONS
[CELL BIOLOGY AND CHEMISTRY]
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INTRODUCTION
The present research study has been emphasizing on the structure of enzymes and their
interconnection with the functions. Furthermore, in the study discussion has also been included
regarding the lock and key and inducted fit models of enzyme action.
Structure of enzyme and how their structure is linked to the function
Enzymes are typically considered as protein macromolecules which have a sequence with
amino acid and which is typically 100-500 long like amino acid. It also has a defined three-
dimensional structure which also shows the relation with catalysts (What Is Enzyme Structure
and Function, 2017). Primary structure: In this structure, enzyme is developed by amino acids which has a
direct link with peptide bonds in a linear chain.
 Secondary structure: It includes the hydrogen in the amino acid and it also combines
carboxyl group of each amino acid so as to form hydrogen bond. This includes a chain
that can fold up on itself can form α-helix (Pollard, Earnshaw, Lippincott-Schwartz and
Johnson, 2016).
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 Tertiary structure: This shows the folding up of the linear chain wherein protein can
comes in association with different chains (Clark, 2013).
The structure of enzyme is related to the function as well wherein the functional groups
binds together to reach with the molecules. In order to catalyse the reaction, the active site
includes small number of catalytic amino acids (Othmer, 2013). At the same time, the substrate
molecule can also bind to the active site through no-covalent interactions.
Concept of activation energy
The concept of activation energy includes small degree of energy that is further
associated into the reactant molecules so that the energy level can become equivalent to
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threshold value. It shows the difference between average energy and threshold energy of the
reactant molecules (Drost-Hansen and Clegg, 2013). The basic formula of activation energy is:
Activation energy = Threshold energy – Average energy of the reactant
It is also identified that in default room temperature, most of the reactant molecules are
possessed with fewer amount of energy as compared to the threshold value. However, it also
states that if energy is provided in the way of giving heat and light, then the reactant molecule
enthral this energy so as to become equal with the threshold value (Lynch and Sazer, 2014).
Therefore, they start changing into products. In this realm, it can be said that when the activation
energy is less, the reaction of action of activation energy becomes greater. Activation energy is
also the level of dynamism that is essential to reach at each transition state. Further, the way
through which the activation energy needs to get pushed because reactions are typically heat
energy. There are two major reaction that is considered in the activation energy and which also
shows the combination of high and slow reaction.
The lock and key and inducted fit models of enzyme action
Lock and Key Theory shows the hypothesis that the active site of the enzyme is like a
‘lock’ in which substrate fits like a ‘key’. This shows that the shape of the active site and the
substrate molecules are complementary. Thus, this represents that the enzyme molecules play
essential role in holding the substrate. At the same time, it also forms the unusual compound
which makes the enzyme substrate complex in nature (Larance and Lamond, 2015).
However, on the other hand induced fit theory states that the active site does not include
any rigid lock and key confirmation. It also depicts that the binding of the substrate molecule
with the enzyme molecule brings modification in the shape of active site. This aids in enhancing
the flexibility of substrate molecules. This is termed as induced fit. This holds possibility to
occur because of the presence of flexibility of protein molecules (Jordan, Neumann and Sowers,
2013).
Effect of three external factors on enzyme activity
The activity of enzymes are greatly impacted because of changes in environmental
aspects and changes in that also transforms the degree that changes the rate of reaction that is
produced by the presence of enzyme.
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 Temperature: Increase in the temperature enhances the kinetic energy wherein molecules
holds greater position. For instance – in a fluid, there exists various collisions randomly
that occur among diverse molecules in each of the unit time (Hay, 2013). Contrary to this,
when the level of temperature increases, it brings vibrational energy that also results in
giving strains which has huge holding power.
 pH- Acidity and Basicity: It is apparent that pH is useful in measuring the level of acidity
and basic level of the solution. This is a great indication that depicts Hydroxide Ion
concentration. Acid solutions possess more pH values (below 7); however basic solutions
have pH values above 7. This also specifies deionised water which becomes neutral in
that stage (Factors affecting Enzyme Activity, 2016). Change in pH above and below
level immediately causes a reduction and at the same time it decrease in the rate of
reaction as enzyme molecules have active sites who does not have complementary shapes
according to the substrate.
 Concentration: This depicts that when the level of enzyme and substrate concentration
changes, it alters the rate of reaction and at the same time, it also leads to develop
enzyme- catalyst reaction. This also includes managing the forces present in a cell in
which organism regulates its enzyme activity to form into metabolism (Drost-Hansen and
Clegg, 2013). Nonetheless, it also changes the concentration of the substance that further
changes the rate of reaction and this happens in limiting factor. Thus, in the case of
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Temperature
pH-
Acidity
and
Basicity
Concentratio
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limiting factor, the level of concentration enhances up to a certain point. But, when
changes occur in the reaction, it also leads to reduce the substrate that is used in the
substrate molecule. This is the highest area that shows the reaction in initial stage;
however it keeps on changing when the enzyme presents in the experimental situation
(Demidchik, 2015).
CONCLUSION
Concluding the study, it can be said that Enzymes are also regarded as catalyst which
chemically mixes up with other mechanism and as a result it leads to biochemical reaction.
Thus, in this respect, researcher has stated the effect of external factors on enzyme activity.
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REFERENCES
Clark, R. ed., 2013. The molecular and cellular biology of wound repair. Springer Science &
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Demidchik, V., 2015. Mechanisms of oxidative stress in plants: from classical chemistry to cell
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Drost-Hansen, W. and Clegg, J. S. eds., 2013. Cell-Associated Water: Proceedings of a
Workshop on Cell-Associated Water Held in Boston, Massachusetts, September, 1976.
Academic Press.
Factors affecting Enzyme Activity. 2016. [Online]. Available through:
<https://alevelnotes.com/Factors-affecting-Enzyme-Activity/146>. [Accessed on 18th
April 2017].
Hay, E. D. ed., 2013. Cell biology of extracellular matrix. Springer Science & Business Media.
Jordan, C. A., Neumann, E. and Sowers, A. E. eds., 2013. Electroporation and electrofusion in
cell biology. Springer Science & Business Media.
Larance, M. and Lamond, A.I., 2015. Multidimensional proteomics for cell biology. Nature
Reviews Molecular Cell Biology. 16(5). pp.269-280.
Lynch, M. and Sazer, S., 2014. Evolutionary cell biology: two origins, one
objective. Proceedings of the National Academy of Sciences. 111(48). pp.16990-16994.
Othmer, H. ed., 2013. Nonlinear Oscillations in Biology and Chemistry: Proceedings of a
meeting held at the University of Utah, May 9–11, 1985 (Vol. 66). Springer Science &
Business Media.
Pollard, T. D., Earnshaw, W. C., Lippincott-Schwartz, J. and Johnson, G., 2016. Cell biology.
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What Is Enzyme Structure and Function?. 2017. [Online]. Available through:
<https://www.thebalance.com/what-is-enzyme-structure-and-function-375555>.
[Accessed on 18th April 2017].
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