transketolase or transaldolase activity

Definition

Target type: molecularfunction

Catalysis of the transfer of an aldehyde or ketonic group from one compound (donor) to another (acceptor). [GOC:jl, ISBN:0198506732]

Transketolase and transaldolase are both enzymes involved in the pentose phosphate pathway, a crucial metabolic route that provides reducing power in the form of NADPH and precursors for nucleotide biosynthesis.

Transketolase catalyzes the transfer of a two-carbon unit from a ketose donor to an aldose acceptor, resulting in the formation of a new ketose and an aldose. This reaction is essential for the conversion of xylulose-5-phosphate to ribose-5-phosphate, a key precursor for nucleotide synthesis.

Transaldolase, on the other hand, facilitates the transfer of a three-carbon unit from a ketose donor to an aldose acceptor. This reaction plays a vital role in the interconversion of fructose-6-phosphate and erythrose-4-phosphate, which are crucial intermediates in the pentose phosphate pathway.

Both transketolase and transaldolase require thiamine pyrophosphate (TPP) as a cofactor. TPP acts as a carrier of the two-carbon or three-carbon units during the transfer reactions.

In summary, transketolase and transaldolase play indispensable roles in the pentose phosphate pathway by enabling the interconversion of sugars, providing NADPH for reductive biosynthesis, and generating precursors for nucleotide synthesis.'
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Proteins (1)

Compounds (4)