Question

What is net ATP production in glycolysis?

Answer 1

Hint: An oxygen-independent metabolic pathway is a glycolysis. The large occurrence of glycolysis suggests that it is an ancient pathway of metabolism.

Complete Answer:
- The metabolic pathway that transforms glucose $C_{6}H_{12}O_{6}$ into pyruvate, $CH_{3}COCOO$- (pyruvic acid) and a hydrogen ion, $H^+$, is glycolysis. To form the high-energy molecules ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine dinucleotide), the free energy produced in this process is used.
- Glycolysis is a series of ten reactions that are catalysed by enzymes. It is possible to transform most monosaccharides, such as fructose and galactose, to one of these intermediates. Rather than simply being used as steps in the overall reaction, the intermediates can also be directly useful.
- Indeed, under the oxygen-free conditions of the Archean oceans, the reactions that constitute glycolysis and its parallel mechanism, the pentose phosphate mechanism, occur metal-catalysed, even in the absence of enzymes. If the glucose is transformed into glucose-6-phosphate and fructose-6-phosphate is transformed to fructose 1,6 bisphosphate, two ATPs are initially invested. In two more reactions, four ATPs are released (each two) when—
i) 1,3 biphosphoglycerate is converted into 3 phosphoglycerides and 3 phosphoglycerate.
(ii) phosphoenolpyruvate converts to pyruvate. So 2 ATPs in glycolysis are the net gain.

Note: Glycolysis in the cytosol happens in most species. The Embden - Meyerh of - Parnas (EMP) pathway, which was discovered by Gustav Embden, Otto Meyerhof, and Jakub Karol Parnas, is the most common form of glycolysis. Other pathways, such as the Entner - Doudoroff pathway and separate heterofermentative and homofermentative pathways, are often referred to in glycolysis. The discussion here will, however, be restricted to the pathway between Embden - Meyerh of - Parnas.