Analyze the chemical reactions that take place when a biological catalyst combines with a reactant (substrate) to form an unstable intermediate.
This should be in your text and/or notes. I assume you can pick any biological reaction you choose.
To analyze the chemical reactions that take place when a biological catalyst combines with a substrate to form an unstable intermediate, we need to understand the role of biological catalysts, also known as enzymes, in facilitating chemical reactions in living organisms.
Enzymes are proteins that act as catalysts, meaning they increase the rate of a chemical reaction without being consumed. Enzymes achieve this by lowering the activation energy, which is the energy needed to initiate a reaction. By lowering the activation energy, enzymes speed up biochemical reactions and allow them to occur under mild conditions compatible with living systems.
When an enzyme combines with a substrate, several steps occur to form an unstable intermediate. Let's break down the process:
1. Substrate binding: The substrate, which is the molecule upon which the enzyme acts, binds to the active site on the enzyme. The active site is a region of the enzyme that specifically binds to the substrate, creating an enzyme-substrate complex.
2. Formation of enzyme-substrate complex: The enzyme-substrate complex is formed when the substrate is bound to the active site of the enzyme. This complex brings the substrate molecules in close proximity, often in an optimal orientation for the reaction to occur.
3. Chemical reaction: Once the enzyme and substrate are in the complex, chemical reactions occur between them. Enzymes can catalyze a wide range of reactions, including breaking bonds (hydrolysis), forming bonds (condensation), rearranging atoms, or transferring functional groups.
4. Rearrangement of chemical bonds: During the chemical reaction, the enzyme modifies the substrate's chemical bonds. This process can involve the breaking and forming of covalent or non-covalent bonds. The specific rearrangement of bonds depends on the type of enzyme and substrate involved.
5. Formation of unstable intermediate: At some point during the reaction, an unstable intermediate may be formed. An unstable intermediate is a transient intermediate compound that is highly reactive and has a higher free energy than either the substrate or the product. It is a key step in the reaction, allowing the transformation of the substrate into the product.
6. Release of product: After the formation of the unstable intermediate, further chemical reactions occur within the enzyme-substrate complex, leading to the conversion of the unstable intermediate into the final product(s) of the reaction. Once the product is formed, it is released from the active site, allowing the enzyme to bind to another substrate and continue the catalytic cycle.
It is important to note that the exact mechanism and steps involved in enzyme-catalyzed reactions can vary depending on the enzyme and the specific reaction. Enzymes are highly efficient and specific catalysts, and their reaction mechanisms are finely tuned to meet the needs of the biological system in which they operate.
In summary, when a biological catalyst (enzyme) combines with a substrate, several steps occur, including substrate binding, formation of enzyme-substrate complex, chemical reaction, rearrangement of chemical bonds, formation of an unstable intermediate, and release of product. These steps collectively enable enzymes to accelerate biochemical reactions, essential for the functioning of living organisms.