The document summarizes the pentose phosphate pathway (PPP), also known as the phosphogluconate pathway or hexose monophosphate shunt. It has two main functions: providing NADPH and producing pentoses. The PPP occurs mainly in the liver, lactating mammary glands, and other tissues. It has an oxidative and non-oxidative phase and involves enzymes that oxidize glucose-6-phosphate to produce NADPH and pentose phosphates through a series of reactions. Deficiencies in enzymes in this pathway can cause hemolytic anemia, neurological disorders, and other conditions.

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2. LaY Out
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Other names
Definition
Occurence & Tissue Distribution
Biomedical Importance
Metabolic Pathway
Clinical Correlates
Regulation
Differences with EM Pathway
References
Acknowledgements
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3. Phosphogluconate Pathway
Pentose Cycle
Hexose Monophosphate Pathway or Shunt
Warburg-Dickens-Lipman Pathway
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4.  The
process which brings
about oxidation &
decarboxylation at C-1 of
Glucose 6phosphate, reducing NADP+
to NADPH & producing
Pentose Phosphates.
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6. Liver
Lactating Mammary Gland
Adrenal Cortex
Gonads
Adipose Tissue
Erythrocytes
Lens & Cornea
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7. It has 2 main functions:
Provides NADPH
Provides PENTOSES
Though there is oxidation of
Glucose,but it is NOT meant for
Energy.
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8.  It
1)
2)
has 2 Phases:
Oxidative Phase
Non-Oxidative Phase
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9. Glucose 6-Phosphate
Glucose 6-phosphate NADP+
Dehydrogenase
Mg++
NADPH+H
6-phosphogluconolactone
6-phosphoglucolactonase
H2O
Mg++ H+
6-phosphogluconate
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10. 6-phosphogluconate
6-phosphogluconate NADP+
Dehydrogenase Mg++
NADPH+H
3-Keto-6-phosphogluconate
D-Ribulose 5-phosphate + CO2
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11. D-Ribulose 5-Phosphate
Phosphopentose
Isomerase
D-Ribose 5-phosphate
D-Ribose-1-P
D-Ribose-1,5-di-P
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12. D-Ribulose-5-P
Phosphopentose
Epimerase
D-Xylulose-5-Phosphate
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13. 2 Particular Enzymes are
required:
1)TRANSKETOLASE
2)TRANSALDOLASE
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14. 1)
Xylulose-5-P+Ribose-5-P
Transketolase
TPP
Sedoheptolose 7-Phosphate +
Glyceraldehyde-3-Phosphate
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15. Sedoheptolose 7-P+G3P
Transaldolase
Fructose 6-Phosphate
+
Erythrose 4-Phosphate
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16. 2)Xylulose 5-P+Erythrose 4-P
Transketolase
TPP
Fructose 6-Phosphate +G3P
Dihydroxy-acetone-P+G3P
Recycles
the Pathway
Glucose-6-P
Fructose-1,6-bi-P
Fructose-6-P
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17. G-6-PD deficiency results in:
Heamolytic Aneamia
Neonatal
Kidney
Jaundice
failure
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18. Mutation
in gene coding for G6PD,
production of NADPH decreases,low
level of reduced glutathione--accumulation of H2O2---RBC’s memb.
bursts---Heamolysis.
Oxidant group of drugs e.g,
Antimalarials,Analgesics,Antipyretics
& Sulpha antibiotics.
Fava beans.
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19.  Genetically
variant form of
Transketolase. It can’t bind
TPP, affecting “transketolation”
reaction.
 Symptoms
are:
 Mental disorders
 Severe memory loss
 Partial paralysis
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20. Results in:
Liver cirrhosis
Male
infertility
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21. Occurs in 3 ways:
a) Ratio of [NADP+][NADPH]
_1st Step is Rate-limiting step catalysed by
G6PD.
b) Increased
HMP Shunt on feeding
high CHO diet & decreased in
Diabetes Mellitus
c)HORMONES:
Insulin & Thyroid hormones
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22.  Occurs
in all
tissues
 Not a multi cyclic
process
 NAD+ is H+
acceptor
 ATP production
 CO2 is never
formed
EM PATHWAY
Occurs
in certain
special tissues
Multi cyclic
process
NADP+
is H+
acceptor
ATP is not
produced
CO2 is produced
HM PATHWAY
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23. Lehninger
Principles of Biochemistry
5th edition,Pg.no 558-563
Biochemistry by Thomas M.Devlin
7th edition,Pg.no 648-652
Harper’s Illustrated Biochemistry 29th
edition,Pg.no 197-204
Medical Biochemistry by MN.Chatterjea
8th edition,Pg.no 354-360
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24. THANK
YOU
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