Embden-Meyerhof pathway Glycolysis: A common biochemical pathway for the fermentation of glucose is glycolysis, also named the Embden-Meyerhof pathway for its major discoverers. Can be divided into three major stages Stage I: A series of preparatory rearrangements: reactions that do not involve oxidation -reduction and do not release energy but that lead to the production from glucose of two molecules of the key intermediate, glyceraldehyde 3 phosphate Stage I: Oxidation-reduction occurs, energy is conserved in the form of aTP, and two molecules of pyruvate are formed Stage Il: A second oxidation-reduction reaction occurs and fermentation products(for example, ethanol and co2 or lactic acid)are formed
Embden-Meyerhof pathway Glycolysis: A common biochemical pathway for the fermentation of glucose is glycolysis, also named the Embden-Meyerhof pathway for its major discoverers. Can be divided into three major stages. Stage I : A series of preparatory rearrangements: reactions that do not involve oxidation-reduction and do not release energy but that lead to the production from glucose of two molecules of the key intermediate, glyceraldehyde 3- phosphate. Stage II: Oxidation-reduction occurs, energy is conserved in the form of ATP, and two molecules of pyruvate are formed. Stage III: A second oxidation-reduction reaction occurs and fermentation products (for example, ethanol and CO2, or lactic acid) are formed
NADH Lactate Pyruvate NADH Acetaldehyde Ethanol pyruvate co Oxaloacetate acetolactate NADH Acetyl-C。A Form Co NADH H co Malate Acetyl-(P)Acetaldehyde Acetoin HO 上烨P~叫 NADH Acetate Ethanol Fumarate 2. 3-butanediol Acetoacetyl-CoA NADH co Succinate Acetone Butyryl-c。A NADH NADH c。A 。 Co Butyraldehyde Butyryl-OP NADH Propionate Isopropanol Butanol Butyrate 1.Lactic acid bacteria (Streptococcus, Lactobacilus), Bacillus 2. Yeast,zym。 nonas 3. Propionic acid bacteria (Propionibacterium) 4. Enterobacter, serratia, Bacilus 5. Enteric bacteria(Escherichia, Enterobacter, salmonella, Proteus) 6. Clostridium
Three type fermentation of Saccharomyces cerevisiae I: pyruvate>acetaldehyde>ethanol II: pH7: glycerol Ill: NaHSO3
Three type fermentation of Saccharomyces cerevisiae I: pyruvate→acetaldehyde→ethanol II: pH7: glycerol III: NaHSO3
Lactic acid fermentation The reduction of pyruvate to lactate Homofermentative(同型发酵的) group: produces only lactic acid as sole pl roduct Heterofermentatiⅳve(异型发酵的 group: produces ethanol, CO2 and lactic acid
Lactic acid fermentation • The reduction of pyruvate to lactate • Homofermentative（同型发酵的） group: produces only lactic acid as sole product • Heterofermentative（异型发酵的） group: produces ethanol, CO2 and lactic acid
6.6 Respiration and Electron Transport Respiration: in which molecular oxygen or some other oxidant serves as the terminal electron acceptor The discussion of respiration deals with both the carbon and electron transformations (1) the biochemical pathways involved in the transformation of organic carbon to CO2 (2) the way electrons are transferred from the organic compound to the terminal electron acceptor, driving ATP synthesis at the expense of the proton motive force
6.6 Respiration and Electron Transport The discussion of respiration deals with both the carbon and electron transformations: • (1) the biochemical pathways involved in the transformation of organic carbon to CO2. • (2) the way electrons are transferred from the organic compound to the terminal electron acceptor, driving ATP synthesis at the expense of the proton motive force. Respiration : in which molecular oxygen or some other oxidant serves as the terminal electron acceptor