Why are substrates specific to enzymes
Enzymes bind with chemical reactants called substrates. There may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. In some reactions, a single-reactant substrate is broken down into multiple products. In others, two substrates may come together to create one larger molecule. Two reactants might also enter a reaction, both become modified, and leave the reaction as two products.
Since enzymes are proteins, this site is composed of a unique combination of amino acid residues side chains or R groups. Each amino acid residue can be large or small; weakly acidic or basic; hydrophilic or hydrophobic; and positively-charged, negatively-charged, or neutral. The positions, sequences, structures, and properties of these residues create a very specific chemical environment within the active site. A specific chemical substrate matches this site like a jigsaw puzzle piece and makes the enzyme specific to its substrate.
Increasing the environmental temperature generally increases reaction rates because the molecules are moving more quickly and are more likely to come into contact with each other. However, increasing or decreasing the temperature outside of an optimal range can affect chemical bonds within the enzyme and change its shape.
If the enzyme changes shape, the active site may no longer bind to the appropriate substrate and the rate of reaction will decrease. Cell Introduction 2. Cell Structure 3. Membrane Structure 4. Membrane Transport 5. Origin of Cells 6. Cell Division 2: Molecular Biology 1. Metabolic Molecules 2. Water 3. Protein 5. Enzymes 6. Cell Respiration 9. Photosynthesis 3: Genetics 1. Genes 2. Chromosomes 3. Meiosis 4. Inheritance 5. Genetic Modification 4: Ecology 1.
Definition noun A feature of enzyme activity with regard to the kind of substrate reacting with an enzyme to yield a product Supplement In an enzyme activity, the substrate must bind with the enzyme to become a catalyst of a chemical reaction. And most enzymes are highly specific particularly to the nature of the substrate they bind to. Substrate specificity is one of the most essential distinctive features of enzyme s. Examples of enzymes showing a very high specificity are biosynthetic enzymes such as those involved in genome replication and expression.
There are certain enzymes that have varying extent of substrate specificity.
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