The difference between a coenzyme and a prosthetic group
Presented by Rania Gamal Sabet To Biochemistry department
Coenzymes A specific type of cofactor, coenzymes, are organic molecules that bind to enzymes and help them function. The key here is that they're organic. Which are simply molecules that contain carbon. Either coenzymes are not really enzymes. As the prefix 'co-' suggests, they work with enzymes. These molecules often sit at the active site of an enzyme and aid in recognizing, attracting, or repulsing a substrate or product. Remember that a substrate is the molecule upon which an enzyme catalyzes a reaction. Coenzymes can also shuttle chemical groups from one enzyme to another enzyme. Coenzymes bind loosely to enzymes, while another group of cofactors do not. Coenzymes bind loosely to the active site of enzymes
Coenzymes examples Enzymes are proteins, coenzymes are small, nonprotein molecules. Coenzymes hold an atom or group of atoms, allowing an enzyme to work. Examples of coenzymes include the B vitamins and S-adenosyl methionine. Vitamins coenzymes All of the water-soluble vitamins and two of the fat-soluble vitamins, A and K, function as cofactors or coenzymes. The active forms of riboflavin, vitamin B2, are the coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). That have precursors of electron-carrying coenzymes.Their main function is to accept and store electrons within proteins. Cofactor Cofactors are not proteins but rather help proteins, such as enzymes, although they can also help non-enzyme proteins as well. Examples of cofactors include metal ions like iron and zinc. The difference between cofactor and coenzyme? Cofactors serve the same purpose as coenzymes, as they regulate, control, and adjust how fast these chemical reactions would respond and take effect in our body. The big difference is that coenzymes are organic substances, while cofactors are inorganic. Prosthetic Groups Prosthetic groups are cofactors that bind tightly to proteins or enzymes. They can be organic or metal ions and are often attached to proteins by a covalent bond. The same cofactors can bind multiple different types of enzymes and may bind some enzymes loosely, as a coenzyme, and others tightly, as a prosthetic group. Some cofactors may always tightly bind their enzymes. The prosthetic groups can also bind to proteins other than enzymes.
. Example of a prosthetic group Prosthetic groups are non-protein components that attach mostly to proteins and assist the protein in various ways. When bound to proteins, prosthetic groups are called holoproteins. Some examples of prosthetic groups are heme, biotin, flavin, iron sulfides, copper and ubiquinone. Main job of prosthetic groups Prosthetic groups are non-protein components that attach mostly to proteins and assist the protein in various ways. Prosthetic groups assist cellular function by participating in cellular respiration and fatty acid synthesis. When bound to proteins, prosthetic groups are called holoproteins. Prosthetic groups are cofactors that bind tightly to proteins or enzymes. They can be organic or metal ions and are often attached to proteins by a covalent bond. The same cofactors can bind multiple different types of enzymes and may bind some enzymes loosely, as a coenzyme, and others tightly, as a prosthetic group. The difference between a prosthetic group and a coenzyme A prosthetic group is firmly attached to a protein and usually cannot be removed during protein purification. A coenzyme is an organic molecule that is less firmly attached. Carbon monoxide binds to isolated heme molecules much more tightly than oxygen. Coenzyme prosthetics A coenzyme prosthetic group is tightly bound to the enzyme and remains bound during the catalytic cycle. The original coenzymes are regenerated during the catalytic cycle. That is mean, a coenzyme substrate is loosely bound to an enzyme and dissociates in an altered form as part of the catalytic cycle.
Differentiate between prosthetic group and co-enzyme. Criteria Prosthetic group Co-enzyme Type of molecule Either metal ions or Small organic small organic molecules. molecules. Binding Tightly-bound or Loosely-bound to the stably-associated enzyme. with the enzyme. Role Assists the Facilitates the functioning of the biological enzyme by binding transformation of the with the apoenzyme. enzyme. Examples Metal ions such as Coenzyme A, biotin, Co, Mg, Cu, Fe and folic acid, vitamin organic molecules B12. such as biotin and FAD.
Prosthetic Group vs. Coenzyme Cofactors are the helper molecules of enzymes. They are not proteins and are either inorganic or organic molecules. Coenzymes and prosthetic groups are two types of helper molecules. A coenzyme is an organic molecule which binds loosely with enzymes to help reactions. A prosthetic group is an organic molecule or a metal iron which binds tightly or covalently with the enzyme to assist chemical reactions. This is the difference between prosthetic group and coenzyme. Both groups are reusable and nonspecific to the enzymes.
Reference: Lakshmi Murmu December 27, 2019avatar Avatar, Toppr December 27, 2019, Samanthi May 20, 2017 Difference between Prosthetic Group and Coenzyme “Cofactor (biochemistry).” Wikipedia. Wikimedia Foundation, 14 May 2017. Web. 17 May 2017.