Page 96 - General Biochemistry
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Chapter 5:
Nucleotides Synthesis and Degradation
Nucleotide Metabolism
PURINE RIBONUCLEOTIDES SYNTHESIS:
Purine ribonucleotides are guanine and adenine that are formed de novo
The First purine derivative formed is Inosine Mono-phosphate (IMP) then
from it AMP and GMP are synthesized
• The purine base is hypoxanthine
Figure 19 purine nucleotides
Synthesis of IMP:
Inosine monophosphate is synthesized from ribose-phosphate through a
complex pathway.
-The source of the carbon no 5 and nitrogen no 4 of the purine ring, come
from different sources, The amino acid glycine will give 2 carbon and 1
nitrogen atoms, glutamine will give 2 nitrogen atoms, aspartic acid will
give1 nitrogen atom, formic acid will give 2 carbon atoms and a carbon
atom from bicarbonate.
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