Classification Of Enzymes And Enzymes

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Coenzyme Coenzymes are small organic molecules that associate to enzyme and whose existence is necessary to the action of those enzymes. Coenzymes belong to the larger group called cofactors. several reactions of substrates are catalyzed by en¬zymes only in the presence of a definite non-protein organic molecule called the coenzyme. Coenzymes unite with the apoenzyme (the pro¬tein part) to form holoenzyme. Fig 1: coenzyme Classification of co-enzymes Coenzymes can be classified into 2 groups according to the way they play a part in an enzymatic reaction: Coenzyme cosubstrate -loosely bound to the enzyme -dissociates from the enzyme in an altered form as part of the catalytic cycle -original form is …show more content…

There are 5 coenzymes involved in its catalytic activity. 1) NAD+ 2) Lipoamide 3) Coenzyme A 4) Thiamine pyrophosphate 5) FAD Role of coenzymes Coenzymes are a type of cofactor and they are bound to enzyme active sites to help with their accurate functioning. Coenzymes which are directly concerned and altered in the course of chemical reactions are measured to be a kind of secondary substrate. This is as they are chemically changed as a result of the reaction unlike enzymes. However unlike the primary substrates, coenzymes can be used by a amount of different enzymes and as such are not specific. For example hundreds of enzymes are able to use the coenzyme NAD. How are coenzymes made? Many coenzymes are derived from vitamins. Table 1 lists vitamins, the coenzymes resulting from them, the type of reactions in which they contribute, and the class of coenzyme. VITAMINS AND COENZYMES. Vitamin Coenzyme Reaction type Coenzyme …show more content…

The molecule ATP (adenosine triphosphate) can function as a coenzyme. When a phosphate group is removed, turning ATP into ADP (adenosine diphosphate), energy is released. Since several chemical reactions require energy, cells can use ATP to give energy to a reaction to help in altering the substrate to product. The substrate can be temporarily phosphorylated, or have an added phosphate group. The phosphate group can then be removed and the product is formed partly through the addition and removal of a phosphate. Fig 2: structure of ATP. 2. Coenzymes frequently have long complex names and are often shortened to abbreviations. Coenzymes with shortened names include: NAD+/NADH, NADP+/NADPH, and FAD/FADH2. These function similarly to ATP, except instead of a molecular group they eliminate or add electrons and hydrogen atoms. therefore, they have two different forms: NAD+ and NADH is the same molecule, except NADH has added hydrogen. Also, the removal or addition of electrons can change their shape, allowing them to bind or dissociate (be removed) from an enzyme they are helping. 3. Their function is typically to accept atoms or groups from a substrate and to transfer them to other molecules. 4. They are less specific than are enzymes and the same coenzyme can act as such in a number of different

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