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Cofactors and coenzyme

In this article we will learn about cofactors and coenzymes and the difference between them.

Introduction

A cofactor is a chemical compound that is not a protein. It is bound to the protein and is required for the protein’s biological activity. They are also known as ‘helper molecules’ because they aid in biochemical transformations. Cofactors are classified into two types:

  • Coenzymes
  • Prosthetic groups

Coenzymes were indeed cofactors that are loosely bound to an enzyme. Prosthetic groups are enzyme cofactors that are tightly bound. In addition, an enzyme can exist without a cofactor, which is known as an apoenzyme. If an enzyme has the cofactor, it is considered complete and is referred to as a holoenzyme.

Coenzyme

A coenzyme is a substance that collaborates with an enzyme to initiate or aid the enzyme’s function. It can be thought of as a helper molecule in a biochemical reaction. Coenzymes are tiny, non proteinaceous molecules that serve as a transfer site for enzymes. They act as intermediate carriers for an atom or group of atoms, allowing a reaction to take place. Coenzymes really aren’t considered to be part of the structure of an enzyme. Cosubstrates are another term for them.

Coenzymes cannot function on their own and must be accompanied by an enzyme. Some enzymes necessitate the presence of multiple coenzymes and cofactors. The B vitamins act as coenzymes, which are required by enzymes to form fats, carbohydrates, as well as proteins. S-adenosylmethionine, which also transfers a methyl group in bacteria as well as eukaryotes and archaea, is an example of a non vitamin coenzyme.

Cofactor

Cofactors are small organic molecules that bind to enzymes to enable or enhance their activity. Metals, such as magnesium, manganese, zinc, molybdenum, cobalt, and copper, are common inorganic cofactors. Inorganic cofactors typically bind to enzymes allosterically, altering the structure and chemical potential of an active site.

Inorganic cofactors can reveal amino acids capable of donating as well as absorbing electrons in the active site, lowering the energy required for the enzyme’s substrate to produce conversion and thus increasing the enzyme’s catalytic activity. Cofactor binding can also alter the structure of the active site, increasing the affinity of the substrate for the active site and thus increasing the rate at which substrates bind, resulting in increased enzymatic activity.

Organic cofactors, also known as coenzymes, are organic molecules that donate or accept electrons from an inorganic molecule and chemical group during enzyme catalysis. Phosphate and methyl groups, as well as lipids and sugars, are examples of chemical groups that can be donated or accepted. Cofactors include all vitamins (for example, nicotinamide adenine dinucleotide (vitamin B3) as well as ascorbic acid (vitamin C). Coenzymes can be energetic molecules (e.g., ATP, ADP), proteins containing iron-sulfur clusters (e.g., metalloproteins), or even DNA nucleotide sugars.

Difference between cofactor and coenzyme

  • Coenzymes are non-protein molecules that are small, organic or metallo organic, and act as an auxiliary for an enzyme’s specific action. Coenzymes are non-protein molecules that are small, organic or metallo organic, and act as an auxiliary for an enzyme’s specific action.
  • Co-enzymes are classified into two types:
  1. Co-substrates: They are temporarily confined to the protein and will be released at some point before being reabsorbed.
  2.  Prosthetic groups: These are permanently bound to the protein.

            Co-factors are classified into two categories:

  1. Cofactors that are organic
  2. Cofactors that are inorganic

Organic cofactors are sometimes subdivided further into coenzymes and prosthetic groups.

  • Coenzymes are non-protein chemical compounds that are complex organic or metallo organic in nature. Cofactors are metallic ions that are not proteins. It could be inorganic ions or organic molecules. 
  •  They serve as a temporary carrier of specific functional groups from one enzyme to the next. Coenzymes entangle to the apoenzyme and help it to function. Co-factors, also known as “helper molecules,” are molecules that aid an apoenzyme during the catalysis of reactions.

Conclusion

Cofactors perform the same function as coenzymes in that they regulate, control, and adjust how quickly these chemical reactions respond and take effect in our bodies. The main distinction is that coenzymes are organic, whereas cofactors are inorganic.

Coenzymes serve as intermediary carriers. This means that they ensure that specific atoms are managed to carry out to the specific group so that the overall reaction can be carried out and completed, so to speak. Cofactors, on the other hand, are needed and required because they are classified as inorganic substances to speed up catalysis.

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Frequently asked questions

Get answers to the most common queries related to the NEET UG Examination Preparation.

Coenzyme A is it a protein or a cofactor?

Ans. The coenzyme could be a non-protein molecule found in nature. Co-factors is another name for coenzyme. More inf...Read full

How are cofactors used during chemical reactions?

Ans. Cofactors are molecules that interact with enzymes during chemical reactions. In general, cofactors are any com...Read full

Give some examples of coenzymes and cofactors.

Ans. A vitamin is an example of a coenzyme. They connect chemical groups between different enzymes. They are also kn...Read full

What should you know about cofactors?

Ans. A cofactor is a chemical compound or metal ion that is not a protein and is required for an enzyme to function ...Read full

How are cofactors removed from enzymes?

Ans. Denaturing an enzyme can be used to remove cofactors. Cofactors, like metal ions, are bonded to enzymes and inc...Read full