CoA biosynthesis

Coenzyme A (CoA) is an important cofactor (acyl-chain carrier) for many cellular functions including the citrate cycle and fatty acid biosynthesis and metabolism. Vitamin B5, also known as pantothenate is the precursor for CoA biosynthesis. Pantothenate synthesis takes place in plants, fungi and some bacteria, whereas animals salvage pantothenate from diet and CoA biosynthesis from pantothenate is present in most organisms. Plasmodium falciparum utilises pantothenate from host and converts it to CoA, whereas Toxoplasma gondii possesses the four enzymes required for the generation of pantothenate from the branched chain amino acid valine. Cryptosporidium species possess the ability to synthesise CoA from pantothenate, but cannot synthesise pantothenate de novo. Of the enzymes involved in the conversion of pantothenate to CoA, pantetheine-phosphate adenylyltransferase is missing in gene models of all three Cryptosporidium species.

 

Enzyme EC Number Gene id
Dephospho-CoA kinase 2.7.1.24 CMU_002250
Pantothenate kinase 2.7.1.33 CMU_015140
Pantothenate kinase 2.7.1.33 CMU_024180
Pantetheine-phosphate adenylyltransferase 2.7.7.3 Missing in annotation
Holo-[acyl-carrier-protein] synthase 2.7.8.7 CMU_011160
Phosphopantothenoylcysteine decarboxylase 4.1.1.36 CMU_042560
Phosphopantothenate-cysteine ligase 6.3.2.5 CMU_017240
Apo-Acyl carrier protein none CMU_013770

 

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Sources and fates of metabolites

 

Substrate Source pathways Product Fate pathways
Pantothenate Host CoA Pyruvate metabolism, Tricarboxylic acid (TCA) cycle
Methylene-THF Recycling of folate THF Recycling of folate
Cysteine Host