Hexose Pentose Pathway and Uronic Acid Pathway

ribose -5- phosphate

Provides the body with ________, which forms phosphoribosyl pyrophosphate (PRPP) for the synthesis of nucleotides and nucleic acids.

Hexose Pentose Pathway

pathway by which glucose is converted to phentose phosphate with production of NADPH

Site of Hexose Pentose Pathway

cytosol of many cells

induces synthesis of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase

insulin

inhibits glucose-6-phosphate dehydrogenase

NADPH

Uronic acid pathway

minor pathway that produces uronic acids

Favism

deficiency of glucose-6-phosphate dehydrogenase (G6PD)

Essential Pentosuria

genetic deficiency of enzyme L-xylulose reductase

main source of NADPH

Hexose Pentose Pathway

glucuronate is converted to

vitamin C (L-ascorbic acid)

Complete oxidation of glucose in HMP produces

6 molecules of CO2 and 12 molecules of NADPH

UDP-glucuronate synthesizes

Glycosaminoglycans (GAGs)

inhibits glucose-6-phosphate dehydrogenase:

NADPH

glucuronate is converted to vitamin C (L-ascorbic acid) in mammals, except

in primates and guinea pigs

UDP-glucuronate is utilized in detoxification reactions such as

phenol

Oxidative Phase of Hexose Pentose Pathway

* irreversible
* glucose-6-phosphate converted to **6 molecules of ribulose-5-phosphate**
* **2 NADPH produced**

Nonoxidative Phase of Hexose Pentose Pathway

* reversible
* 6 molecules of pentoses into **5 molecules of glucose-6-phosphate**

______: provides the body with ribose-5-phosphate, which forms phosphoribosyl pyrophosphate (PRPP)

Pentose Phosphate Pathway