Bacterial synthesis of C3-C5 diols via extending amino acid catabolism

Abstract

Amino acids are naturally occurring and structurally diverse metabolites in biological system, whose potentials for chemical expansion, however, have not been fully explored. Here, we devise a metabolic platform capable of producing industrially important C3-C5 diols from amino acids. The presented platform combines the natural catabolism of charged amino acids with a catalytically efficient and thermodynamically favorable diol formation pathway, created by expanding the substrate scope of the carboxylic acid reductase toward noncognate ω-hydroxylic acids. Using the established platform as gateways, seven different diol-convertible amino acids are converted to diols including 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol. Particularly, we afford to optimize the production of 1,4-butanediol and demonstrate the de novo production of 1,5-pentanediol from glucose, with titers reaching 1.41 and 0.97 g l−1, respectively. Our work presents a metabolic platform that enriches the pathway repertoire for nonnatural diols with feedstock flexibility to both sugar and protein hydrolysates.

Designing the bioproduction of Martian rocket propellant via a biotechnology-enabled in situ resource utilization strategy

“…Therefore, the energy needed to compress, or refrigerate, gaseous methane to a liquid for storage and propulsion is sidestepped. Finally, with respect to bioreachability, several natural and engineered microbes produce C 3 -C 4 diols in high titers and yields 25 , whereas C5 diols production is low 26 , and >C5 diols production has been elusive. In particular, we consider 1,2-pro- 28 , and 2,3-BDO (C 4 ) 29 as Martian rocket propellants, all of which can be biologically synthesized today (Fig.…”

Valorisation of xylose to renewable fuels and chemicals, an essential step in augmenting the commercial viability of lignocellulosic biorefineries

“…One of the major applications of BDO is production of methyl ethyl ketone (MEK), an organic solvent used in production of resins and lacquers. 145,146 Microbial physiology adaptation for BDO pathway is hypothesized to prevent intracellular acidification and balancing the reducing equivalents. Two moles of pyruvate undergo sequential oxidoreductive reactions to form BDO with α-acetolactate, acetoin/diacetyl as intermediates as shown in Figure 6C.…”

Recent advances in biological production of 1,3-propanediol: new routes and engineering strategies

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