A systematic exploration of bacterial form I rubisco maximal carboxylation rates.

Autotrophy is the basis for complex life on Earth. Central to this process is rubisco-the enzyme that catalyzes almost all carbon fixation on the planet. Yet, with only a small fraction of rubisco diversity kinetically characterized so far, the underlying biological factors driving the evolution of fast rubiscos in nature remain unclear.

Autotrophic growth of is achieved by a small number of genetic changes.

Synthetic autotrophy is a promising avenue to sustainable bioproduction from CO. Here, we use iterative laboratory evolution to generate several distinct autotrophic strains. Utilising this genetic diversity, we identify that just three mutations are sufficient for to grow autotrophically, when introduced alongside non-native energy (formate dehydrogenase) and carbon-fixing (RuBisCO, phosphoribulokinase, carbonic anhydrase) modules.

Functional reconstitution of a bacterial CO concentrating mechanism in .

Many photosynthetic organisms employ a CO concentrating mechanism (CCM) to increase the rate of CO fixation via the Calvin cycle. CCMs catalyze ≈50% of global photosynthesis, yet it remains unclear which genes and proteins are required to produce this complex adaptation. We describe the construction of a functional CCM in a non-native host, achieved by expressing genes from an autotrophic bacterium in an strain engineered to depend on rubisco carboxylation for growth.

Conversion of Escherichia coli to Generate All Biomass Carbon from CO.

The living world is largely divided into autotrophs that convert CO into biomass and heterotrophs that consume organic compounds. In spite of widespread interest in renewable energy storage and more sustainable food production, the engineering of industrially relevant heterotrophic model organisms to use CO as their sole carbon source has so far remained an outstanding challenge. Here, we report the achievement of this transformation on laboratory timescales.