4)phosphoketolase pathway (PK) a.Pentose phosphoketolas Pathway xse5-phosphate phosphoketolase acetyl phosphate glyceraldehyde 3-phosphate pyruvate ethanol Lactic acid 1G>→→Lactic acid+ethanol+1ATP+NADPH+H+
4) phosphoketolase pathway (PK) a.Pentose phosphoketolas Pathway G xylulose 5-phosphate acetyl phosphate + glyceraldehyde 3-phosphate phosphoketolase ethanol pyruvate Lactic acid 1 G →→→ Lactic acid + ethanol + 1 ATP + NADPH + H+
b.Hexose phosphoketolas_Pathway (HK) Bifidobacterium bifidum fructose 6-phosphates phosphoketolase Erythrose -4-P acetyl-phosphates fructose 6-phosphates acetokinase xylulose -5-P ribulose-5-P Acetic acid phosphoketolase glyceraldehyde 3-phosphate acetyl-phosphates Lactic acid Acetic acid 1G-→-→→Lactic acid+1.5 Acetic acid+2.5ATP
G fructose 6-phosphates b.Hexose phosphoketolas Pathway (HK) （Bifidobacterium bifidum ） Erythrose - 4-P + acetyl-phosphates phosphoketolase glyceraldehyde 3-phosphate + acetyl-phosphates xylulose -5-P ribulose-5-P Acetic acid phosphoketolase fructose 6-phosphates Lactic acid Acetic acid 1 G →→→ Lactic acid + 1.5 Acetic acid + 2.5 ATP acetokinase
2 fermentantion 1.definitions broader use microorganism to produce useful metabolic product narrower:under anaerobic conditions,be defined as an energy- yielding process using itself metabolic intermediates as the final hydrogen (electron)accepter organic molecules serve as both electron donors and acceptors. trait 1)generates ATP by substrate-level phosphorylation; 2)the glucose is partially oxidized,mostly energy in fermention products 3)lower energy; 4) generates many kinds of fermention products
1. definitions broader ：use microorganism to produce useful metabolic product narrower：under anaerobic conditions, be defined as an energyyielding process using itself metabolic intermediates as the final hydrogen (electron) accepter organic molecules serve as both electron donors and acceptors. trait： 1） generates ATP by substrate-level phosphorylation； 2）the glucose is partially oxidized ，mostly energy in fermention products ； 3）lower energy； 4） generates many kinds of fermention products 2 fermentantion
2.fermentation sorts 1) alcohol fermentation a.yeasts (EMP)2 pyruvate>2 aldehyde +CO2 -→2 ethanol+2ATP condiction:pH 3.5~4.5 without O2 Strain:Saccharomyces cerevisiae,few bacteria(Erwiniaamylovora, Sarcine vintriculi) I.Add NaHSO4 NaHSO4 aldehyde->sulfonic hydroxy aldehyde ii.weak basic (pH 7.5) 2 aldehyde->1 acetate +1 ethanol glycerol fermentation dihydroxyacetone as hydrogen accepter,hydrolyzed to glycerol
2. fermentation sorts 1） alcohol fermentation a. yeasts 1 G 2 pyruvate → 2 aldehyde + CO2 → 2 ethanol + 2 ATP condiction：pH 3.5~4.5 , without O2 Strain：Saccharomyces cerevisiae, few bacteria(Erwinia amylovora, Sarcine vintriculi) I. Add NaHSO4 NaHSO4 + aldehyde → sulfonic hydroxy aldehyde ii.weak basic（pH 7.5） 2 aldehyde → 1 acetate + 1 ethanol glycerol fermentation : dihydroxyacetone as hydrogen accepter, hydrolyzed to glycerol （EMP）
D.bacteria (Zymomonasmobili,Pseudomonas saccharophila) homoalcohol fermentation 1G 2 pyruvate ethanol 1ATP (ED) heteroalcohol fermentation (Thermoanaerobacter ethanolicu) 2 pyruvate (Pyruvate formate lyase formic acids acetyl-CoA Without Pyruvatedecarboxylate aldehyde -ethanol With aldehyde dehydrogenase
b. bacteria (Zymomonasmobili, Pseudomonas saccharophila ) homoalcohol fermentation 1 G 2 pyruvate （ED） ethanol + 1ATP heteroalcohol fermentation (Thermoanaerobacter ethanolicu) 1 G 2 pyruvate （ Pyruvate formate lyase ） aldehyde → ethanol formic acids + acetyl-CoA Without Pyruvatedecarboxylate With aldehyde dehydrogenase