Structure and function of microbial enzymes for carbón recycling: towards sustainable production of added value biomolecules

JAVIER MARCELO GONZÁLEZ; MARIA BELEN LOPEZ; MARIA BELEN OTERINO

Ciudad Autonoma de Buenos Aires

Otro; A. Von Humboldt Colloquium- Shaping the Future of German-Argentinian Scientific Cooperation ? The Role of Curiosity-Driven Research; 2018

A. Von Humboldt

Extremophilic microorganisms constitute life forms that exhibit various metabolic states, being able to obtain carbon from organic compounds or from CO2. They have colonized the most varied ecological niches, including environments with extremes of pH, salinity, temperature, and UV radiation such as the Puna de Atacama, in northern Argentina. The arsenal of metabolic enzymes that allows the proliferation of extremophiles in the most unexpected environments, constitutes a collection of tools of enormous biotechnological value, such as enzymes for the production of biomass in plants and algae from C-neutral sources such as household waste and industrial effluents.Methylobacterium extorquens uses the Serine Pathway to assimilate methanol, which is a carbon neutral source because it comes from CO2 in the atmosphere and not from fossil fuels.Metabolic Engineering allows the design of metabolic pathways that do not exist in Nature to produce biomolecules of interest. For example, a synthetic metabolic pathway that makes it possible to transform a 3-carbon compound (C3) plus bicarbonate (C1) into 2 molecules of Acetyl-CoA (C2): the fundamental ?brick? to produce all kinds of biomolecules, including lipids and biofuels. . All this combining 8 enzymes from 3 different microorganisms: PEPC, MDH, MTK and MCL from the methylotroph Methylobacterium extorquens (blue), GCL & TSR from the enterobacterium Escherichia coli (yellow), and GLK & EN from the photosynthetic cyanobacterium Synechococcus elongatus (green) .X-ray crystallography allows determining the atomic structure of molecules. The molecular details of enzymes can be exploited to understand how they work and to modify their catalytic properties through site-directed mutagenesis.