Engineering Microorganisms for Enhanced CO2 Sequestration

TL;DR: In this article, the authors proposed a method to prevent excessive accumulation of CO2 in the atmosphere, which is known to be dominantly caused by the increased concentration of greenhouse gases.

TL;DR: Integration of bioreactors with electrochemical systems will permit new production opportunities with enhanced productivities and the advantage of using a low-carbon electricity from renewable and sustainable sources.

Abstract: CO2 sequestration engineering is an attractive strategy for achieving carbon- and energy-efficient bioproduction. However, the efficiency of heterotrophic CO2 sequestration is limited by bioproduct dependence and energy deficiency. Here, modular CO2 sequestration engineering was developed to produce target chemicals by integrating synthetic CO2 fixation and CO2 mitigation modules. A synthetic CO2 fixation pathway was designed, and then enhanced by light-driven reducing power using self-assembled cadmium sulfide nanoparticles. Next, a CO2 mitigation switch was designed, and then optimized by light-driven energy via proteorhodopsin. Finally, by integrating CO2 fixation and CO2 mitigation modules, the efficiency of CO2 sequestration was notably enhanced in Escherichia coli and the yields of l-malate and butyrate were increased to 1.48 and 0.79 mol/mol glucose, respectively, reaching theoretical yields. This CO2 sequestration system provides an efficient platform for channelling CO2 into value-added chemicals. Improving the efficiency of carbon yield in heterotrophic microorganisms is desired for biomanufacturing. Now, a product-independent and energy-efficient CO2 sequestration system that maximizes carbon conversion has been developed, as showcased by the production of chemicals reaching their theoretical yields.

TL;DR: The model microalgae and cyanobacteria presented as chassis hosts in synthetic biology, recent advances of their genome editing techniques by CRISPR technology, and potential applications of their metabolic engineering and regulation approaches are examined in this review.

TL;DR: Although microalgae are not yet produced at large scale for bulk applications, recent advances—particularly in the methods of systems biology, genetic engineering, and biorefining—present opportunities to develop this process in a sustainable and economical way within the next 10 to 15 years.

TL;DR: Natural photosynthesis is compared with present technologies for photovoltaic-driven electrolysis of water to produce hydrogen and opportunities in which the frontiers of synthetic biology might be used to enhance natural photosynthesis for improved solar energy conversion efficiency are considered.

TL;DR: This Review addresses the principles, challenges and opportunities of microbial electrosynthesis, an exciting new discipline at the nexus of microbiology and electrochemistry.

TL;DR: The molecular mechanisms that underlie the ability of microorganisms to exchange electrons, such as c-type cytochromes and microbial nanowires, with extracellular minerals and with microorganisms of the same or different species are discussed.