Embden-Meyerhof pathway Glycolysis

A variety of monosaccharides (hexoses or pentoses) can be fermented to produce 2,3-BD (Syu, 2001). In bacterial metabolism, monosaccharides must first be converted to pyruvate before generation of major products. From glucose, pyruvate is formed in a relatively simple manner via the Embden-Meyerhof pathway (glycolysis). In contrast, the production of pyruvate from pentoses must proceed via a combination of the pentose phosphate and Embden-Meyerhof pathways (Jansen and Tsao, 1983). In addition to 2,3-BD, the pyruvate produced from the monosaccharides is then channeled into a mixture of acetate, lactate, formate, succinate, acetoin, and ethanol, through the mixed acid-2,3-BD fermentation pathway (Ji et al., 2011a). 

In contrast with the well-known Embden-Meyerhof-Pamass glycolysis pathway for the conversion of hexose sugars to alcohol, the steps in conversion of ethanol to acetic acid remain in some doubt. Likely, ethanol is first oxidized to acetaldehyde and water (39). For further oxidation, two alternative routes are proposed more likely, hydration of the acetaldehyde gives CH2CH(OH)2, which is oxidized to acetic acid. An alternative is the Cannizzaro-type disproportionation of two molecules of acetaldehyde to one molecule of ethanol and one molecule of acetic acid. Jicetobacter... 

Embden-Meyerhof pathway (Section 29.5) An alternative name for glycolysis. 

Elimination reaction, 138. 383-393 biological examples of, 393 summary of, 393-394 Embden-Meyerhof pathway, 1143-1150 see also Glycolysis... 

You will probably be familiar with glycolysis (the Embden-Meyerhof pathway, Figure 1.20) from previous studies at school perhaps, so let s use this important pathway to illustrate some points in the recommended strategy. 

An alternative pathway to the Embden-Meyerhof pathway of glycolysis for conversion of carbohydrates to pyruvate is the pentose-phosphate pathway (Fig. 5.13). Its main role is not ATP production but to provide NADPH for fat synthesis, and pentoses (in particular, D-ribose-5-phosphate) for nucleic acid synthesis. The pathway can also convert pentoses to hexoses, which can then be further metabolised by glycolysis. With regard to cestodes, a... 

Two metabolic patterns are discernible from the results. Carbon atoms 2, 1, and 7 of shikimate (VI) are derived almost equally from G-1,6, G-2,5, and G-3,4, respectively. In the Embden-Meyerhof pathway of hexose metabolism (see Fig. 2), D-fructose 1,6-diphosphate is cleaved to 1,3-dihydroxy-2-propanone phosphate (G-1,2,3) and D-glycerose 3-phosphate (G-4,5,6), and the two trioses are interconverted by triose phosphate isomerase. The observed randomization of label between Cl and C6, C2 and C5, and C3 and C4 of hexose therefore implies that C2, Cl, and C7 of shikimate are derived from a 3-carbon intermediate of glycolysis. The small but significant preponderance of G-6 over G-1, of G-5 over G-2, and, presumably, of G-4 over G-3, can be explained by recent observations that, in the aldolase cleavage of D-fructose 1,6-diphosphate, the 1,3-dihy-... 

LAB are non-respiring microorganisms, principally generating ATP by fermentation of carbohydrates coupled to substrate-level phosphorylation. The two major pathways for the metabolism of hexoses are homofermentative or glycolysis (Embden-Meyerhof pathway), in which lactic acid is virtually the only end-product, and heterofermentative (phosphoketolase pathway), in which other end-products such as acetic acid, C02, and ethanol are produced in addition to lactic acid (Axelsson et al., 1989 Kandler, 1983 Zourari et al., 1992). 

The reaction in glycolysis is often referred to as the Embden-Meyerhof pathway. 

The major pathway by which glucose is metabohsed to give energy has two stages. The first, known as glycolysis, can occur under anaerobic conditions and results in the production of pyruvate. The sequence of reactions (Fig. 9.4), often referred to as the Embden-Meyerhof pathway, takes place in the cell cytoplasm. 

---