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. 1971 May;47(5):672–675. doi: 10.1104/pp.47.5.672

The Pentose Phosphate Pathway in Relation to Fat Synthesis in the Developing Castor Oil Seed 1

P K Agrawal a,2, D T Canvin a
PMCID: PMC396748  PMID: 16657682

Abstract

Slices of 25- to 28-day-old developing castor bean endosperm were incubated with various 14C- and 3H-labeled substrates to determine the amount of glucose dissimilated in the pentose phosphate pathway and to determine the use of the reduced nucleotides so produced in fatty acid synthesis. Ten to 12% of the metabolized glucose traversed the pentose phosphate pathway, and reduced nicotinamide adenine dinucleotide phosphate (NADPH) production would be sufficient to supply 51 to 68% of the reducing equivalents required for fat synthesis. However, using 3H-NADPH produced from 3-3H-glucose as a tracer, it was found that only 40% of the NADPH produced in the pentose phosphate pathway was used in fat synthesis. Thus the actual contribution of the reducing equivalents generated from the pentose phosphate pathway to fat synthesis was 20 to 27% of that required. Because of the methods and assumptions, this value represents a minimal estimate of NADPH used in fat synthesis, and the actual contribution may be somewhat higher. However, tritium from 3H-NADH generated from 1-3H-ethanol was incorporated into fatty acids, and it is contended that NADH may supply a large proportion of the reducing equivalents necessary for fat synthesis in this tissue.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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