Enzymes

• Michaelis-Menten kinetics states that the velocity of an enzyme's catalysis approaches a maximum (Vmax) as the concentration of substrate increases.
• When the substrate enters the active site, it undergoes chemical change (catalysis).
• The active site of an enzyme has a specific shape that fits only one type of molecule, called its substrate.
• Enzyme-substrate complex is formed when the substrate binds to an enzyme.
• Enzyme kinetics describes the relationships between the concentration of substrates, products, and enzymes in enzymatic reactions and how these relationships influence the rate of the reactions.
• Enzymes are made up of long chains of amino acids that fold into complex three-dimensional structures.
• Km can be used to compare the affinity of different enzymes for their substrates.
• The Michaelis constant, Km, is defined as the substrate concentration at which Vmax/2 occurs.
• Enzymes with lower Km values have higher affinities for their substrates.
• The product leaves the active site to be used or broken down further.
• Enzymes are proteins with specific shapes that allow them to bind only certain molecules called substrates.
• Km value represents the affinity of an enzyme for its substrate.
• Products are released from the enzyme.
• Chemical reaction occurs at the active site of the enzyme.
• An enzyme is made up of amino acids arranged into polypeptide chains.
• Substrates fit into the active sites on the surface of the protein like keys fitting into locks.
• Enzymes are proteins with a unique three-dimensional structure that allows them to bind to their substrates.
• Active sites on enzymes have a unique structure that allows them to interact with specific substrates.
• A low Km indicates high affinity, while a high Km indicates low affinity.
• Active sites can be occupied by more than one substrate molecule simultaneously.
• Amino acid side groups can be polar or nonpolar, charged or uncharged, hydrophilic or hydrophobic.
• Vmax represents the maximum velocity at which an enzyme catalyzes a reaction.
• Substrates must fit perfectly into the active site of an enzyme for the reaction to occur.
• Increasing temperature can increase reaction rates by increasing the frequency of collisions among reactant particles.
• Increasing temperature increases the speed of most biochemical reactions by increasing the frequency of collisions among reacting particles.
• Enzymes can be inhibited by substances that block their activity or prevent them from binding to their substrates.
• Allosteric regulation involves regulatory proteins called effectors that bind to allosteric sites on enzymes and either activate or deactivate them.
• Noncompetitive inhibitors bind to another part of the enzyme than the active site and alter its shape so that the substrate cannot bind.
• Competitive inhibitors bind to the same site as the substrate but do not undergo chemical change with it.
• Enzymes have a unique three-dimensional structure determined by their amino acid sequence.
• The shape of an enzyme's active site is complementary to its specific substrate(s), allowing it to bind tightly and catalyze the desired reaction.
• Enzymes are proteins that act as biological catalysts, lowering activation energy barriers and facilitating chemical reactions.
• The Michaelis-Menten equation describes how the rate of an enzymatic reaction depends on both the concentration of the enzyme (E) and its substrate (S).
• Factors affecting enzyme activity include temperature, pH, cofactors/coenzymes, activators/inhibitors, and allosteric regulation.
• At high concentrations of substrate, the rate becomes limited only by the availability of free enzyme molecules.
• Increasing the amount of enzyme increases the maximum velocity (Vmax) of the reaction, while increasing the substrate concentration increases the initial velocity until Vmax is reached.
• Denaturation disrupts the tertiary structure of enzymes, rendering them unable to function properly.
• Enzymes can be denatured (unfolded) by high temperatures, extreme pH levels, or organic solvents.
• Enzymes increase the rate of biochemical reactions without being consumed themselves.
• Hydrophobic interactions play a crucial role in protein folding by driving nonpolar side chains into the interior of the folded molecule.