Saturday, December 08, 2012

Patent to issue on -- Methods and Systems for Chemoautotrophic Production of Organic Compounds --

Published US application 20120064622 (serial no. 13/285919) titled Methods and Systems for Chemoautotrophic Production of Organic Compounds received a "notice of allowance" on 13 November 2012. The case, assigned to GINKGO BIOWORKS, had been filed under the "Green Tech" program on 31 October 2011.

The specification of the case includes


[0003] Heterotrophs are biological organisms that utilize energy from organic compounds for growth and reproduction. Commercial production of various carbon-based products of interest generally relies on heterotrophic organisms that ferment sugar from crop biomass such as corn or sugarcane as their energy and carbon source [Bai, 2008]. An alternative to fermentation-based bio-production is the production of carbon-based products of interest from photosynthetic organisms, such as plants, algae and cyanobacteria, that derive their energy from sunlight and their carbon from carbon dioxide to support growth [U.S. Pat. No. 7,981,647]. However, the algae-based production of carbon-based products of interest relies on the relatively inefficient process of photosynthesis to supply the reducing power needed for production of organic compounds from carbon dioxide [Larkum, 2010]. Moreover, commercial production of carbon-based products of interest using photosynthetic organisms relies on reliable and consistent exposure to light to achieve the high productivities needed for economic feasibility; hence, photobioreactor design remains a significant technical challenge [Morweiser, 2010].

[0004] Chemoautotrophs are biological organisms that utilize energy from inorganic energy sources such as molecular hydrogen, hydrogen sulfide, ammonia or ferrous iron, and carbon dioxide to produce all organic compounds necessary for growth and reproduction. Existing, naturally-occurring chemoautotrophs are poorly suited for industrial bio-processing and have therefore not demonstrated commercial viability for this purpose. Such organisms have long doubling times (minimum of approximately one hour for Thiomicrospira crunogena but generally much longer) relative to industrialized heterotrophic organisms such as Escherichia coli (twenty minutes), reflective of low total productivities. In addition, techniques for genetic manipulation (homologous recombination, transformation or transfection of nucleic acid molecules, and recombinant gene expression) are inefficient, time-consuming, laborious or non-existent.

[0005] Accordingly, the ability to endow an otherwise heterotrophic organism with chemoautotrophic capability would significantly enable more energy- and carbon-efficient production of carbon-based products of interest. Alternatively, the ability to add one or more additional or alternative pathways for chemoautotrophic capability to an autotrophic or mixotrophic organism would enhance its ability to produce carbon-based products on interest.


[0006] Systems and methods of the present invention provide for efficient production of renewable energy and other carbon-based products of interest (e.g., fuels, sugars, chemicals) from inorganic carbon (e.g., greenhouse gas) using inorganic energy. As such, the present invention materially contributes to the development of renewable energy and/or energy conservation, as well as greenhouse gas emission reduction.

Although the specification mentions the -- relatively inefficient process of photosynthesis --, chemoautotrophic reduction of CO2 is less energetically efficient than photoautotrophic reduction. Separately, for reference, the specification cited US Patent No. 7,981,647 which is assigned to Joule Unlimited, which patent in turn cites US Patent No. 6699696 to Woods, currently CEO of Algenol, which '696 patent had disclosed photosynthetic conversion of CO2 to ethanol.

There was a response made on 29 October 2012 to a non-final rejection by one Fang Xie, registration number L0591, representing GINKGO. Concerning a written description rejection, there was a citation to the CAFC case of Falkner v. Inglis, 448 F.3d 1357 (CAFC 2006). There was also a response to a 102 rejection over work by James Liao of UCLA (WO 2011/088425). The work of Liao, which is PCT/US2011/021436 , is titled -- ELECTRO-AUTOTROPHIC SYNTHESIS OF HIGHER ALCOHOLS -- with abstract

The disclosure provides a process that converts CO2 to higher alcohols (e.g. isobutanol) using electricity as the energy source. This process stores electricity (e.g. from solar energy, nuclear energy, and the like) in liquid fuels that can be used as high octane number gasoline substitutes. Instead of deriving reducing power from photosynthesis, this process derives reducing power from electrically generated mediators, either H2 or formate. H2 can be derived from electrolysis of water. Formate can be generated by electrochemical reduction of CO2. After delivering the reducing power in the cell, formate becomes CO2 and recycles back. Therefore, the biological CO2 fixation process can occur in the dark.

The written opinion for the Liao PCT indicated a lack of inventive step over prior work by Atsumi (Nature Biotechnology 2009) and Ishizaki (2001).

**Cross-reference to the work of Peter Doran and others discussed in
Life abounds in Antarctic lake sealed under ice;
Lake Vida's cold brine has yielded a bounty of microbes.


Post a Comment

<< Home