\"Metabolic contest\", a new way to control carbon source preference

Allmann, S.; Wargnies, M.; Cahoreau, E.; Biran, M.; Plazolles, N.; Pauline, M.; Pineda Ramirez, E.; Kulyk, H.; Asencio, C.; Villafraz, O.; Riviere, L.; Tetaud, E.; Rotureau, B.; Mourier, A.; Portais, J.-C.; Bringaud, F.

doi:10.1101/800839

bioRxiv · 10.1101/800839

\"Metabolic contest\", a new way to control carbon source preference

Allmann, S.·Wargnies, M.·Cahoreau, E.·Biran, M.·Plazolles, N.·Pauline, M.·Pineda Ramirez, E.·Kulyk, H.·Asencio, C.·Villafraz, O.·Riviere, L.·Tetaud, E.·Rotureau, B.·Mourier, A.·Portais, J.-C.·Bringaud, F.

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Abstract

Microorganisms must make the right choice for nutrient consumption to adapt to their changing environment. As a consequence, bacteria and yeasts have developed regulatory mechanisms involving nutrient sensing and signaling, allowing to redirect cell metabolism to maximize the consumption of an energy-efficient carbon source. Here, we report a new mechanism, named \"metabolic contest\", for regulating the use of carbon sources without nutrient sensing and signaling. In contrast to most microorganisms, trypanosomes show a glycerol-to-glucose preference that depends on the combination of three conditions: (i) the sequestration of both metabolic pathways in the same subcellular compartment, here in the peroxisomal-like organelles named glycosomes; (ii) the competition for the same substrate, here ATP, with the first enzymatic step of the glycerol and glucose metabolic pathways being both ATP-dependent (glycerol kinase and hexokinase, respectively) and (iii) an unbalanced activity between the competing enzymes, here the glycerol kinase activity being ~80-fold higher than the hexokinase activity.

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Allmann, S., Wargnies, M., Cahoreau, E., Biran, M., Plazolles, N., Pauline, M., Pineda Ramirez, E., Kulyk, H., Asencio, C., Villafraz, O., Riviere, L., Tetaud, E., Rotureau, B., Mourier, A., Portais, J.-C., Bringaud, F.. 2019-10-10. \"Metabolic contest\", a new way to control carbon source preference. https://doi.org/10.1101/800839

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