Sugar nucleotides biosynthetic pathway

Figures 9.10 and 9.11 show the biosynthetic pathways for AMP and GMP Phosphorbosylpyrophosphate (PRFP) is the source of the sugar group of the pyrimidine and purine nucleotides, A nucleotide consists of the purine or pyrimidine base connected to ribose phosphate, PRPP is synthesized as shown in Figure 9.12.

Biosynthetic pathways for nucleotide sugars. [Reproduced with permission from H. Schachter, Glycoprotein biosynthesis. In The Glycoconjugates, Vol. 2, M.I. Horowitz and W. Pigman (Eds). Academic Press,... 

Scheme 22 The whole biosynthetic pathway of sugar nucleotides. ATP, adenosine triphosphate Gal-1 -P, galactose-1-phosphate UTP, uridine triphosphate UDP, uridine diphosphate NAD, nicotinamide adenine dinucleotide Fru, fructose AcCoA, acetyl coenzyme-A PEP, phosphoenolpyruvate CTP, cytidine triphosphate NADP, nicotinamide adenine dinucieotide phosphate GTP, guanosine triphosphate.

The majority of the orfs located at the GI have similarities to genes that encode enzymes involved in modifying sugars of various polysaccharide biosynthetic pathways of Gram-negative bacteria. Only the functions of orfA (involved in nucleotide activation of 4-amino-4,6-dideoxyhexose (viosamine)) and fgtA... 

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