S65: Sustainable production of industrial chemicals using microbial biocatalysts: 1,4-Butanediol

Genomatica has established an integrated computational/experimental metabolic engineering platform to design, create, and optimize novel high-producing organisms and bioprocesses.  Here we present the use of our platform to develop E. coli strains for the production of the industrial chemical 1,4-butanediol (BDO) from glucose and sucrose. BDO is a four-carbon diol that currently is manufactured exclusively through various petrochemical routes. It is part of a large volume family of solvents and polymer intermediates with an overall market opportunity exceeding $4.0B. Therefore, this product represents an opportunity to make a significant impact on the replacement of traditional petrochemical processes with benign bioprocesses using renewable feedstocks.

Here we describe application of this technology platform to design and construct a high-performing microorganism capable of producing BDO from carbohydrates for the first time. We used our computational tools both to elucidate the most favorable biopathway that could be used to produce this non-natural product, and to engineer the host strain to direct cellular carbon and energy resources into this pathway. After design-based production of the biocatalyst, our models facilitated the analysis of fermentation data to evaluate performance. Systems biology approaches including microarrays, ¹³C-flux analysis, proteomics, and metabolomics were applied in conjunction with the models to characterize the strain, identify targets for further improvement, and optimize the fermentation process. The presentation will show how significant progress was made in BDO titer, production rate, and yield through model-guided strain and process improvement, ultimately resulting in an economically attractive process that was validated at demonstration plant scale.