(i) It provides alternative route for carbohydrate breakdown.

(ii) It generates NADPH molecules which are used as reductants in biosynthetic processes under conditions when NADPH molecules are not generated by photosynthesis. It is therefore, especially important in non-photosynthetic tissues such as in differentiating tissues, ger­minating seeds and during periods of darkness. Production of NADPH is not linked to ATP generation in pentose phosphate pathway.
(iii) It provides Ribose sugars for the synthesis of nucleic acids.
(iv) It plays important role in fixation of CO2 in photosynthesis through Ribulose-5-Phosphate. (Ribulose 1, 5-bisphosphate derived from Ribulose-5-Phosphate is the primary acceptor of CO2 in photosynthesis).
(v) It provides Erythrose-4-phosphate which is required for the synthesis of shikimic acid. The latter is precursor of aromatic ring compounds.
(In addition to the above pathway for the oxidation of carbohydrates, still other routes have been identified in some micro-organisms and enzyme systems discovered. In all such cases the initial steps of glucose oxidation differ from glycolysis but ultimately pyruvic acid is produced.
On such alternative pathway is Entner Doudoroff Pathway which is shown in Fig. 16-19. In this pathway the carboxylic group of pyruvic acid is derived from carbon No. 1 of glucose molecule (in glycolysis it was derived from C-No. 3 or 4.).
Pentose phosphate pathway
Entner-Doudoroff Pathway

Related Posts:

  • Amino Acids Structure of an Amino Acid Amino acids are the monomers that make up proteins. Each amino acid has the same fundamental structure , which consists of a central carbon atom, also known as the alpha (α) carbon… Read More
  • Double Helix structure of DNA A Double-Helix Structure DNA has a double-helix structure, with sugar and phosphate on the outside of the helix, forming the sugar-phosphate backbone of the DNA. The nitrogenous bases are stacked in the interior in pairs, … Read More
  • Bioinorganic Chemistry Notes PDF Download Writing the bioinorganic chemistry exam notes was a true delight. For the first time I had the opportunity to study from a book written by doctors here at this medical school presenting the subject in the way THEY would … Read More
  • Absorption of Fats Digestion of Fats Absorption of Fats: Several theories have been proposed for the mechanism of absorption of fats after digestion. The important theories are: A. Lipolytic hypoth­esis. B. Partition theory. C. More r… Read More
  • Metabolic Significance of HMP Shunt 1. CO2 is the characteristic product in this pathway which is not formed in Embden- Meyerhof pathway. This product is uti­lized for the synthesis of fatty acid and purine bases etc. 2. The reduced NADP (NADPH) forme… Read More

0 Comments:

Powered by Blogger.

Visitors

198444
Print Friendly Version of this pagePrint Get a PDF version of this webpagePDF


 download University Notes apps for android

Popular Posts

Flag Counter