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So I am writing a short paper on how one can produce Succinic acid from glycerol. I have to find a microorganism which can do that. I have found the following microorganism, which are traditionally being used for fermentation: Anaerobiospirillum succiniciproducens, Actinobacillus succinogenes, Mannheimia succiniciproducens and recombinant Escherichia coli strains. But the problem is that whatever article I find, they are written with respect to Glucose.

Does anyone know any article/paper/hints or some information they can share?

I just need to understand which organism can be used to do the fermentation, and how much succinic acid can be made from it.

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Glycerol has 3 carbon atoms and succinic acid has 4. So you need (apart from some redox reactions) a way to add another carbon atom.

Also, succinic acid appears in the citric acid cycle. What you have to research are anaplerotic reactions. When you remove any of the metabolites (like succinic acid) from the cycle, you have to replenish them. One way is to turn pyruvate (3 carbons) into oxaloacetate (4 carbons), as shown in the wikipedia article on anaplerotic reactions:

$$\ce{pyruvate + HCO3− + ATP -> oxaloacetate + ADP + P_i + H2O}$$

Then, you have to find a pathway from glycerol to pyruvate. Here is a schematic of glycerol metabolism:

enter image description here

Source: https://www.researchgate.net/publication/224950286_Effect_of_impurities_in_biodiesel-derived_waste_glycerol_on_the_performance_and_feasibility_of_biotechnological_processes/figures?lo=1

As you can see, it is possible to turn glycerol into pyruvate fairly directly (using reactions of glycolysis).

To put everything together, you just need an organism that secretes succinic acid, and make sure that these pathways are turned on sufficiently that most of the provided glycerol gets metabolized to succinic acid. As this involved oxidation, the organism has to have access to oxygen or some other oxidation agent.

UPDATE

Prompted by Andrew's comment, I found a paper where they optimize succinate production from glucose. As you can see from the scheme above, glycerol can be funneled into glycolysis by two enzymes (using one ATP for phosphorylation and one NAD+ for oxidation). The enzymes used for the remainder of the reaction (and to provide NADPH via the pentosephosphate pathway) are shown in the figure from the paper below. You would need to provide some glucose to feed in the pentosephosphate pathway to have sufficient NADPH, or invoke some other pathways:

enter image description here

Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4983090/figure/Fig1/?report=objectonly

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    $\begingroup$ Succinic acid can be produced through oxidative or reductive reactions. The high-yield succinic acid-producing bacteria use both, balancing them so that no oxygen is needed. In addition to using substrate-level phosphorylation, some of these organisms can even gain ATP through coupling of fumarate reduction to oxidative phosphorylation. $\endgroup$
    – Andrew
    Dec 17, 2019 at 18:30
  • $\begingroup$ @Andrew Based on your comment, I found ncbi.nlm.nih.gov/pmc/articles/PMC4983090/pdf/…. They start with glucose, though, not glycerol. $\endgroup$
    – Karsten
    Dec 17, 2019 at 18:47
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    $\begingroup$ As you pointed out in your answer, glycerol is readily converted to the glycolytic intermediate DHAP, so the carbon source is essentially independent of the succinic acid production. Only difference is stoichiometry due to different redox state. $\endgroup$
    – Andrew
    Dec 17, 2019 at 19:27
  • $\begingroup$ 1) glucose is not required for sufficient NADPH. E. coli can grow on glycerol as a sole carbon source. If NADPH availability limits growth, many strategies are available to increase production. See frontiersin.org/articles/10.3389/fmicb.2015.00742/full. 2) the scheme lacks the oxidative pathway to succinic acid (via the normal direction of the TCA cycle), which is important for balancing the redox equivalents. $\endgroup$
    – Andrew
    Dec 17, 2019 at 20:06
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    $\begingroup$ I used to work in industrial fermentation and metabolic engineering. So probably a bit more prior knowledge. . . $\endgroup$
    – Andrew
    Dec 17, 2019 at 20:24

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