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Published on: January 23, 2019
Synthesis of methyl halides from biomass using engineered microbes
Travis S Bayer1, Daniel M Widmaier, Karsten Temme
1Department of Pharmaceutical Chemistry, University of California, San Francisco, MC 2540, Room 408C, 1700 4th Street, San Francisco, California 94158-2330, USA.
Journal of the American Chemical Society
|April 22, 2009
Summary
Researchers engineered methyl halide transferase (MHT) enzymes for industrial production. This advancement enables sustainable methyl halide synthesis from agricultural waste, offering a greener alternative for chemical and fuel precursors.
Area of Science:
- Biotechnology
- Synthetic Biology
- Biocatalysis
Background:
- Methyl halides are vital industrial chemicals and fuel precursors.
- Natural production by organisms yields are too low for industrial needs.
- Methyl halide transferase (MHT) enzymes catalyze methyl group transfer from S-adenosyl methionine (SAM) to halides.
Purpose of the Study:
- To identify and engineer novel methyl halide transferase (MHT) enzymes for efficient industrial production.
- To develop a sustainable bioproduction platform for methyl halides using non-food agricultural biomass.
Main Methods:
- Synthetic metagenomic approach to synthesize 89 putative MHT genes.
- Screening of MHT library in Escherichia coli for halide production rates.
- Engineering of high-activity MHT in Saccharomyces cerevisiae and co-culture with Actinotalea fermentans.
Main Results:
- 56% of synthesized MHT genes showed activity on chloride, 85% on bromide, and 69% on iodide.
- Engineered MHT in yeast achieved 190 mg/L-h productivity from glucose and sucrose.
- Successful methyl halide production from unprocessed lignocellulosic biomass (switchgrass, corn stover, bagasse, poplar) using co-culture.
Conclusions:
- The study demonstrates the potential of engineered MHT enzymes for industrial methyl halide production.
- A symbiotic co-culture system enables the utilization of diverse agricultural waste streams.
- This approach offers a sustainable and scalable method for producing valuable chemicals from non-food biomass.
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