What is the Difference Between Transaldolase and Transketolase?
🆚 Go to Comparative Table 🆚Transaldolase and transketolase are two enzymes involved in the non-oxidative phase of the pentose phosphate pathway, a metabolic pathway that takes place parallel to glycolysis and generates NADPH and ribose-5-phosphate for nucleotide synthesis. The main differences between these two enzymes are:
- Carbon transfer: Transketolase transfers a two-carbon unit from a ketose donor to an aldose acceptor, while transaldolase transfers a three-carbon unit between two sugar molecules.
- Reaction mechanism: The transaldolase reaction begins with aldol cleavage, which is the cleavage of a bond in a β-hydroxy ketone or aldehyde (an aldol). Transketolase, on the other hand, simply cleaves off the ketone group from the substrate and does not perform an aldol cleavage.
- Cofactors: Transketolase requires thiamine pyrophosphate (TPP) as a cofactor, while transaldolase does not.
- Substrates: Transaldolase catalyzes the conversion of sedoheptulose 7-phosphate and glyceraldehydes 3-phosphate, whereas transketolase catalyzes the conversion of xylulose 5-phosphate and ribose 5-phosphate.
In summary, transaldolase and transketolase are both involved in the pentose phosphate pathway, but they differ in their carbon transfer reactions, reaction mechanisms, cofactors, and substrates.
Comparative Table: Transaldolase vs Transketolase
Transaldolase and transketolase are two enzymes that participate in the pentose phosphate pathway, a metabolic pathway that generates NADPH and ribose-5-phosphate for nucleotide synthesis. Here is a comparison table highlighting the differences between these two enzymes:
Feature | Transaldolase | Transketolase |
---|---|---|
Function | Catalyzes the transfer of a three-carbon glycolaldehyde unit from a ketose donor to an aldose acceptor | Catalyzes the transfer of a two-carbon ketol unit from a ketose donor to an aldose acceptor |
Cofactor | Pyridoxal phosphate (PLP) dependent | Thiamine pyrophosphate (vitamin B1) dependent |
Substrates | Sedoheptulose 7-phosphate and glyceraldehydes 3-phosphate | Xylulose 5-phosphate and ribose 5-phosphate |
Gene Coding | TALDO1 gene codes for transaldolase | TKT gene codes for transketolase |
In summary, transaldolase transfers a three-carbon unit, while transketolase transfers a two-carbon unit. Additionally, transaldolase is a pyridoxal phosphate (PLP)-dependent enzyme, and transketolase is a thiamine pyrophosphate (vitamin B1)-dependent enzyme.
- Ketose vs Aldose
- Hydrolase vs Transferase
- Aldohexose vs Ketohexose
- Lyases vs Transferases
- Aldehyde vs Ketone
- Alkaptonuria vs Phenylketonuria
- Reductase vs Oxidoreductase
- Phosphorylase vs Phosphatase
- Hexokinase vs Glucokinase
- Aldol Addition vs Aldol Condensation
- Transamination vs Deamination
- Transcription vs Translation
- Kinase vs Phosphorylase
- Polyhydroxy Aldehydes vs Polyhydroxy Ketone
- Alpha-Amylase vs Alpha-Glucosidase
- Transition vs Transversion
- ALT vs AST
- Aldehyde vs Alcohol
- Reductive Amination vs Transamination