Enzymatic Synthesis of [5-14C]Ribose

✍ Scribed by P.O.J. Ogbunude

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 48 KB
• Volume: 300
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1006/abio.2001.5196

✦ Synopsis

14 C-labeled ribose, essential in tracing the metabolic route of ribose, is not commercially available. Custom synthesis is expensive and out of reach of low funded laboratories particularly in sub-Saharan African countries where funding of basic research is very low. Tracing of the metabolic route of ribose is important because ribose can either enter the nonoxidative pentose phosphate pathway or is used for the biosynthesis of nucleotides and amino acids. The pentose phosphate pathway has been proposed as a potentially important target for chemotherapy against parasitic protozoa (1).

In this report, a simple and reproducible method for the synthesis of [5-14 C]ribose of high purity is described. In the method, [6-14 C]glucose (sp act, 56 mCi/mmol; isotope concentration, 20 Ci) was enzymatically converted to [5-14 C]phosphoribosyl 1-pyrophosphate ([5-14 C]PRPP) 1 using enzymes of the pentose phosphate pathway (PPP). The labeled PRPP was dephosphorylated with a combination of inorganic pyrophosphatase (EC 3.6.1.1) and alkaline phosphatase (EC 3.1.3.1) to yield [5-14 C]ribose with a similar specific activity but an isotope concentration of 5.2 Ci.