Phosphorylation
In biology, -ribose must be phosphorylated by the cell before it can be used. Ribokinase catalyzes this reaction by converting -ribose to -ribose 5-phosphate. Once converted, -ribose-5-phosphate is available for the manufacturing of the amino acids tryptophan and histidine, or for use in the pentose phosphate pathway. The absorption of -ribose is 88–100% in the small intestines (up to 200 mg/kg/hr).
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