Name the class of enzyme that usually catalyze the following reaction :
S – G + S# → S + S# – G
Wher

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Question

Name the class of enzyme that usually catalyze the following reaction :
S – G + S# → S + S# – G
Where, G → a group other than hydrogen
S → a substrate
S# → another substrate

Accepted Answer

Correct Answer: D — TransferaseStep-by-step Solution:The reaction S–G + S# → S + S#–G shows the transfer of a chemical group G (other than hydrogen) from one substrate (S) to another (S#). This type of reaction — group transfer — is catalyzed by Transferases (EC Class 2).Evaluating all enzyme classes:Oxidoreductases (EC 1): Catalyze oxidation-reduction reactions; transfer of electrons/hydrogen. Example: dehydrogenases, oxidases, reductases, peroxidases.Transferases (EC 2) — CORRECT: Catalyze transfer of functional groups (other than hydrogen) from one molecule (donor/substrate) to another (acceptor/substrate). Sub-classes based on group transferred: aminotransferases (transfer amino groups — e.g., transaminases/AST, ALT), kinases (transfer phosphate groups from ATP), methyltransferases (transfer methyl groups), acetyltransferases (transfer acetyl groups), glycosyltransferases (transfer sugar groups).Hydrolases (EC 3): Catalyze hydrolysis reactions — cleavage of bonds using water. Example: proteases (peptide bonds), lipases (ester bonds), amylases (glycosidic bonds), nucleases (phosphodiester bonds).Lyases (EC 4): Catalyze cleavage of C–C, C–O, C–N, C–S bonds by elimination (not hydrolysis or oxidation), producing double bonds or rings, or the reverse addition reactions. Example: decarboxylases, dehydratases, aldolases, synthases (without ATP).Isomerases (EC 5): Catalyze intramolecular rearrangements. Example: mutases (transfer groups within same molecule), epimerases, isomerases.Ligases (EC 6): Join two molecules together using energy from ATP hydrolysis. Example: DNA ligase, amino acyl-tRNA synthetase, pyruvate carboxylase, glutamine synthetase.Extended Explanation:Important transferase examples in NEET biology: Aminotransferases (Transaminases) — transfer amino groups from amino acids to keto acids (e.g., glutamate + oxaloacetate ⇌ α-ketoglutarate + aspartate); Clinically important: AST (Aspartate aminotransferase) and ALT (Alanine aminotransferase) — elevated in liver disease; Kinases — transfer phosphate group from ATP to substrate: Hexokinase (glucose → glucose-6-phosphate), Protein kinases (signal transduction); DNA methyltransferases — methylate cytosine in CpG islands (epigenetic regulation); Acetylcholinesterase — actually a hydrolase (hydrolyzes acetylcholine). The IUB/IUBMB classification of enzymes into six classes (Oxidoreductases, Transferases, Hydrolases, Lyases, Isomerases, Ligases) is a fundamental concept in biochemistry.Key Concepts: Enzyme classification (six classes), transferases (EC class 2), group transfer reactions, kinases, aminotransferases, phosphotransferases, contrast with hydrolases and ligases.

Name the class of enzyme that usually catalyze the following reaction : S – G + S# → S + S# – G Where, G → a group other than hydrogen S → a substrate S# → another substrate

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Name the class of enzyme that usually catalyze the following reaction : S – G + S# → S + S# – G Where, G → a group other than hydrogen S → a substrate S# → another substrate

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