Isobutanol production by combined and metabolic engineering.

The production of the biofuel, isobutanol, in faces limitations due to alcohol toxicity, product inhibition, product recovery, and long-term industrial feasibility. Here we demonstrate an approach of combining both with metabolic engineering to produce isobutanol. The production of α-ketoisovalerate (KIV) was conducted through CRISPR mediated integration of the KIV pathway in bicistronic design (BCD) in and inhibition of competitive valine pathway using CRISPRi technology.

Genome-wide CRISPR-Cas9 screen reveals a persistent null-hyphal phenotype that maintains high carotenoid production in Yarrowia lipolytica.

Yarrowia lipolytica is a metabolic engineering host of growing industrial interest due to its ability to metabolize hydrocarbons, fatty acids, glycerol, and other renewable carbon sources. This dimorphic yeast undergoes a stress-induced transition to a multicellular hyphal state, which can negatively impact biosynthetic activity, reduce oxygen and nutrient mass transfer in cell cultures, and increase culture viscosity. Identifying mutations that prevent the formation of hyphae would help alleviate the bioprocess challenges that they create.

Improved soluble expression and use of recombinant human renalase.

Electrochemical bioreactor systems have enjoyed significant attention in the past few decades, particularly because of their applications to biobatteries, artificial photosynthetic systems, and microbial electrosynthesis. A key opportunity with electrochemical bioreactors is the ability to employ cofactor regeneration strategies critical in oxidative and reductive enzymatic and cell-based biotransformations. Electrochemical cofactor regeneration presents several advantages over other current cofactor regeneration systems, such as chemoenzymatic multi-enzyme reactions, because there is no need for a sacrificial substrate and a recycling enzyme.

Electrochemical Bioreactor Technology for Biocatalysis and Microbial Electrosynthesis.

Two seemingly distinct fields, industrial biocatalysis and microbial electrosynthesis, can be viewed together through the lens of electrochemical bioreactor technology in order to highlight the challenges that exist in creating a versatile platform technology for use in chemical and biological applications. Industrial biocatalysis applications requiring NAD(P)H to perform redox transformations often necessitate convoluted coupled-enzyme regeneration systems to regenerate reduced cofactor, NAD(P)H from oxidized cofactor, NAD(P). Renewed interest in continuously recycling the cofactor via electrochemical reduction is motivated by the low cost of performing electrochemical reactions, easy monitoring of the reaction progress, and straightforward product recovery.

Improved strategies for electrochemical 1,4-NAD(P)H regeneration: A new era of bioreactors for industrial biocatalysis.

Industrial enzymatic reactions requiring 1,4-NAD(P)H to perform redox transformations often require convoluted coupled enzyme regeneration systems to regenerate 1,4-NAD(P)H from NAD(P) and recycle the cofactor for as many turnovers as possible. Renewed interest in recycling the cofactor via electrochemical means is motivated by the low cost of performing electrochemical reactions, easy monitoring of the reaction progress, and straightforward product recovery. However, electrochemical cofactor regeneration methods invariably produce adventitious reduced cofactor side products which result in unproductive loss of input NAD(P).