In this section
@article{Yunus:2021:10.1101/2021.07.08.451587,
author = {Yunus, IS and Anfelt, J and Hudson, EP and Jones, PR},
doi = {10.1101/2021.07.08.451587},
title = {Synthetic metabolic pathways for conversion of CO<sub>2</sub> into secreted short-to medium-chain hydrocarbons using cyanobacteria},
url = {http://dx.doi.org/10.1101/2021.07.08.451587},
year = {2021}
}
TY - JOUR
AB - <jats:title>Abstract</jats:title><jats:p>The objective of this study was to implement direct sunlight-driven conversion of CO<jats:sub>2</jats:sub> into a naturally excreted ready-to-use fuel. We engineered four different synthetic metabolic modules for biosynthesis of short-to medium-chain length hydrocarbons in the model cyanobacterium <jats:italic>Synechocystis</jats:italic> sp. PCC 6803. In module 1, the combination of a truncated clostridial n-butanol pathway with over-expression of the native cyanobacterial aldehyde deformylating oxygenase resulted in small quantities of propane when cultured under closed conditions. Direct conversion of CO<jats:sub>2</jats:sub> into propane was only observed in strains with CRISPRi-mediated repression of three native putative aldehyde reductases. In module 2, three different pathways towards pentane were evaluated based on the polyunsaturated fatty acid linoleic acid as an intermediate. Through combinatorial evaluation of bioreaction ingredients it was concluded that linoleic acid undergoes a spontaneous non-enzymatic reaction to yield pentane and hexanal. When <jats:italic>Synechocystis</jats:italic> was added to the bioreaction, hexanal was converted into 1-hexanol, but there was no further stimulation of pentane biosynthesis. For modules 3 and 4, several different acyl-ACP thioesterases were evaluated in combination with two different decarboxylases. Small quantities of 1-heptene and 1-nonene were observed in strains expressing the desaturase-like enzyme UndB from <jats:italic>Pseudomonas mendocina</jats:italic> in combination with C8-C10 preferring thioestersaes. When UndB instead was combined with a C12-specific ‘<jats:italic>Uc</jats:italic>FatB1 thioesterase, this resulted in ten-fold increase of alkene biosynthesis. When UndB was replaced with the light-dependent FAP decarboxylase, both undecane and tridecane accumulated, a
AU - Yunus,IS
AU - Anfelt,J
AU - Hudson,EP
AU - Jones,PR
DO - 10.1101/2021.07.08.451587
PY - 2021///
TI - Synthetic metabolic pathways for conversion of CO<sub>2</sub> into secreted short-to medium-chain hydrocarbons using cyanobacteria
UR - http://dx.doi.org/10.1101/2021.07.08.451587
ER -
Interested in studying a PhD at the Department of Life Sciences? Find out more about postgraduate research opportunties.