In vitro 5-phosphoribosyl 1-pyrophosphate-independent salvage biosynthesis of ribo- and deoxyriboadenine nucleotides
Biochimica Et Biophysica Acta
|November 26, 2009
Abstract:
The pools of free ribose 1-phosphate and deoxyribose 1-phosphate have been measured in Bacillus cereus. It is shown that crude extracts of the same organism can actively utilize the sugar phosphates to convert adenine to ATP and deoxyATP, via a 'salvage' pathway, involving adenine ribosylation (or deoxyribosylation), followed by multiple phosphorylation steps. The biosynthetic pathway operates even in the presence of excess P(i') thus showing that purine nucleoside phosphorylases may function in vivo, contrary to what is generally assumed, as anabolic rather than catabolic enzymes.
Keywords:
Bacillus cereus metabolismnucleotide salvage pathwaypurine nucleoside phosphorylasesribosylation processMore Related Videos
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