Bioenergetics is the study of energy flow and energy transformation through living organisms and their environment. It is a very important aspect in the field of Biochemistry that combines work with the body and the mind to help people resolve their emotional problems and realize more of their potential for pleasure and joy in living. The mind and body are functionally identical because in our everyday life, our body uses up energy in performing tasks and activities. Energy in the human body is used to create work and power. The activation of energy is affected by so many factors in our body, examples of which are; the acid-base balance, the temperature, the movement of substances in and out the cells and the atmospheric pressure in the body. The energetic processes of the body are related to the state of aliveness of the body. The more alive one is, the more energy one has and vice versa. Every stress (physical or emotional) produces a state of tension in the body. Normally, the tension disappears when the stress is relieved.
The Energy of Activation is the amount of energy which must be added to a reaction to allow it to go forward. Enzymes decrease the energy of activation. The rate that a reaction occurs is called the Reaction Velocity. Catalysts increase the speed of a reaction by lowering the reaction's energy of activation.
Enzymes are protein catalysts which require a vitamin or mineral cofactor such as metal ions. They increase the rate of a reaction between a thousand and a million times he uncatalyzed rate. Enzymes also lower the temperature at which reactions take place to a temperature compatible with life. They catalyze reactions by decreasing the free energy of activation. Examples of enzymes are a follows; Isomerase, the enzyme that converts one isomer to another, Epimerase, an enzyme that converts one epimer to another, Carboxylase, an enzyme that adds carboxyl group to a molecule, the Kinase which catalyzes reactions by adding or removing nucleoside triphosphates and the enzyme Dehydrogenase which catalyzes the removal of hydrogen.
The intermediate product of an enzyme catalyzed reaction is the Enzyme-Substrate complex. A Substrate is the substance which is recognized by the enzyme and is transformed into the product by the reaction. The Active site is the catalytic site of an enzyme and binds the specific substrate. The attraction between an enzyme and substrate is called Affinity. The binding site of an enzyme may be so specific that it recognizes and binds to only one optical isomer of a given molecule; or maybe less specific and recognize several closely related molecules. The Specificity of which follows two theories: "The Lock and Key Theory" which states that substrate and enzyme always fit each other; and the " Induced Fit Theory" which states that the substrate and enzyme fit only at binding.
Isoenzymes are enzymes which have different amino acid sequences, but catalyze the same reactions. They have different electrophoretic mobilities and are made of different proteins. A Holoenzyme is an enzyme that requires a co-factor to be active and its protein part is called the Apoenzyme. The Apoenzyme binds to a Co-factor to form a Holoenzyme.
An Allosteric Enzyme contains another site, different from the active site at which an effector binds. Positive effectors increase the rate at which the enzyme will catalyze the reaction while negative effectors slow the rate. These enzymes are often the first step or branch point in a metabolic pathway, with the product of the pathway serving as a negative effector and the excess substrates as the positive effectors. An Allosteric enzyme may increase or inhibit substrate binding. Substrate binding to one site can alter other sites. The plot of substrate concentration versus the velocity of the reaction if plotted in a graph draws a sigmoidal curve and does no follow the classical hyperbolic curve which is the Michaelis-Menten Curve. Homotropic enzyme substrate molecules cause enzyme to have a conformational change, which increases the binding of other substrate molecules and the velocity. The Heterotropic enzyme substrate molecules have its positive effectors as activators and its negative effectors as inhibitors.
Phosphorylation is the process of activating or inactivating regulatory enzymes. It is catalyzed and activated by phosphorylase kinase. It is deactivated by phosphatase.
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An enthusiastic author from the Big City of the South and a Graduate of Gullas College of Medicine, Banilad, Cebu, Philippines.