Biochemical and synthetic biology approaches to improve photosynthetic CO2-fixation.
Erb TJ, Zarzycki J.
Current Opinion in Chemical Biology, Volume 34, October 2016, Pages 72–79 – PDF
There is an urgent need to improve agricultural productivity to secure future food and biofuel supply. Here, we summarize current approaches that aim at improving photosynthetic CO2-fixation. We critically review, compare and comment on the four major lines of research towards this aim, which focus on (i) improving RubisCO, the CO2-fixing enzyme in photosynthesis, (ii) implementing CO2-concentrating mechanisms, (iii) establishing synthetic photorespiration bypasses, and (iv) engineering synthetic CO2-fixation pathways.
Synthetic metabolism: metabolic engineering meets enzyme design
Erb TJ, Jones PR, Bar-Even A.
Current Opinion in Chemical Biology, Volume 37, April 2017, Pages 56-62 – LINK
Metabolic engineering aims at modifying the endogenous metabolic network of an organism to harness it for a useful biotechnological task, for example, production of a value-added compound. Several levels of metabolic engineering can be defined and are the topic of this review. Basic ‘copy, paste and fine-tuning’ approaches are limited to the structure of naturally existing pathways. ‘Mix and match’ approaches freely recombine the repertoire of existing enzymes to create synthetic metabolic networks that are able to outcompete naturally evolved pathways or redirect flux toward non-natural products. The space of possible metabolic solution can be further increased through approaches including ‘new enzyme reactions’, which are engineered on the basis of known enzyme mechanisms. Finally, by considering completely ‘novel enzyme chemistries’ with de novo enzyme design, the limits of nature can be breached to derive the most advanced form of synthetic pathways. We discuss the challenges and promises associated with these different metabolic engineering approaches and illuminate how enzyme engineering is expected to take a prime role in synthetic metabolic engineering for biotechnology, chemical industry and agriculture of the future.