enzymes

• The ability of enzymes to catalyze reactions depends on their native conformation, and they will lose their catalytic activity if they are denatured
• Enzymes interact with specific molecules and bind to ligands called substrates, converting them rapidly into different chemically modified molecules called products while remaining unchanged during the entire process
• Enzymes mediate almost all the biochemical processes taking place in the cells of the body for the other proteins to also fully carry out their functions
• Without enzymes, many bodily processes would be affected, and life could not exist
• Enzymes are classified according to the reactions they catalyze and are mostly named by simply adding the suffix “-ase” to the word that describes their specific activity
• Enzymes are naturally produced in the body and perform important tasks in muscle building, DNA synthesis, gene expression, and digestion, among others
• Enzymes is a large class of proteins that function in catalyzing or speeding up chemical reactions
• Digestive enzymes

  • amylase
  • lipase
• Although heat could hasten the rate of reaction, given the normal conditions of the biological systems, it can denature proteins, kill cells, and speed-up reactions that are not needed to proceed instead. Enzymes address this dilemma for living organisms by providing an alternative energetically favorable pathway for the specific molecules they catalyze.
• Enzymes enhance reaction rate by lowering energy barriers called the free energy of activation or activation energy (EA). This is the amount of energy that separates the reactants and the products or the “energy difference between that of the reactants and a high-energy intermediate that occurs during the formation of the product” (Ferrier, 2014, p. 111). Therefore, for reactants to become products, they must absorb enough thermal energy from the surroundings to reach a high-energy unstable condition also known as the transition state which enables them to overcome the energy barrier (see Figure 4). Since the energy barrier is too high, most of the spontaneous chemical reactions not acted upon by enzymes occur very slowly.
• Enzymes are naturally produced in the body and they perform important tasks in muscle building, DNA synthesis, gene expression, and digestion, among others. Without enzymes, many bodily processes would be affected, hence, life could not exist. Digestive enzymes particularly amylase, lipase, and protease are hydrolases. Amylase catalyzes the breakdown of starch into sugars. Lipase catalyzes the hydrolysis of fats. Meanwhile, protease cleaves peptide bonds between proteins through hydrolysis to form smaller polypeptides or amino acids.
• Enzymes have a binding site called active site which is a region that corresponds to the contours of the reactant molecules (substrates) that it acts on (see Figure 6). This is where catalysis of the chemical reaction occurs (Alberts et al., 2014). The activation energy needed for the conversion of these substrates into products significantly lowers down. This is because the enzyme binds to the substrates in such a way that would ensure that the transition state can be easily reached. However, there are also other specific various mechanisms the enzyme uses to lower the activation energy and speed up the reactions (Reece
• A simple enzymatic reaction involves a substrate binding to the enzyme’s active site forming an enzyme-substrate complex. The enzyme changes its conformation for the best fit with the substrate. Upon reaching the transition state and overcoming the energy barrier, the product dissociates from the enzyme. The enzyme can catalyze another molecule
• Enzymes decrease the activation energy required for a given chemical reaction to occur
• The activation energy needed for the conversion of substrates into products significantly lowers down when enzymes are involved
• Most metabolic reactions are reversible, thus, enzymes could catalyze either forward or reverse reactions
• Enzymes act only on very specific substrates due to their specificity
• Enzymes bind to substrates to ensure the transition state can be easily reached and use various mechanisms to lower the activation energy and speed up reactions
• Enzymes are proteins
• Enzymes


  • Have diverse functions that support the continuity of life
  • Catalysis happens when a substrate binds to its corresponding active site in the enzyme, forming an enzyme-substrate complex, energetically favoring its conversion into products after reaching an unstable transition state
  • Enzymes are neither used up nor altered after a certain reaction, allowing them to act upon all their other substrates
• Enzymes are proteins that play a key role in various metabolic pathways by speeding up reactions through lowering the activation energy