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<div>Please provide your area of interest and pathway feedback</div>
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<div>Solanum tuberosum thiamine biosynthesis</div>
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<div>There are two errors in this pathway because the described pathway is based on data from E. coli that do not reflect what is happening in plants. </div>
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<div>First, it shows conversion of thiamine monophosphate to thiamine diphosphate, but this reaction does not occur in plants (for a Review see Goyer 2010 Phytochemistry 71, 1615-1624). Instead thiamine monophosphate is dephosphorylated to thiamine by a yet-to-be-characterized
enzyme, then pyrophosphorylated by thiamine pyrophosphokinase (see Ajjawai et al 2007 Plant Mol Biol 65, 151-162).</div>
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<div>Second, 4-methyl-5-hydroxyethylthiazole phosphate is not synthesized from deoxy-xylulose-5-phosphate in plants but from NAD, glycine, and a sulfur donor (a cysteine located on the enzyme 4-methyl-5-hydroxyethylthiazole phosphate synthase – see Chatterjee
et al 2011 Nature).</div>
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<div>Hope this helps.</div>
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<div>Aymeric</div>
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