Abstract: Methods and microorganisms are genetically engineered to continuously produce ethylene by microbial fermentation, particularly by the microbial fermentation of a gaseous substrate. The microorganisms are C1-fixing. Further, the gaseous substrate comprises CO2 and an energy source. The production of ethylene can be improved by varying promoters or nutrient limiting means.

Abstract: The disclosure relates to methods of capturing carbon by microbial fermentation of a gaseous substrate comprising CO into one or more first products which, in turn, may be incorporated into an article of manufacture or one or more second products. Further, the disclosure relates to improving carbon capture and/or efficiency.

Abstract: The invention provides methods and systems for the production of at least one product from the microbial fermentation of a gaseous susbtrate, wherein the gaseous substrate is derived from a biomass liquefaction process. The invention provides a method for improving efficiency of the fermentation by passing biomass accumulated in the fermentation process to the biomass liquefaction process for conversion to a gaseous substrate. In a particular aspect of the invention, the biomass liquefaction process is selected from pyrolysis or torrefaction.