BioChem - DOS

Engineering the iron-oxidizing chemolithoautotroph Acidithiobacillus ferrooxidans for biochemical production

Biotechnology and bioengineering

Kernan, Timothy; Majumdar, Sudipta; Li, Xiaozheng; Guan, Jingyang; West, Alan C.; Banta, Scott

<P><B>ABSTRACT</B></P><P>There is growing interest in developing non&#8208;photosynthetic routes for the conversion of CO<SUB>2</SUB> to fuels and chemicals. One underexplored approach is the transfer of energy to the metabolism of genetically modified chemolithoautotrophic bacteria. <I>Acidithiobacillus ferrooxidans</I> is an obligate chemolithoautotroph that derives its metabolic energy from the oxidation of iron or sulfur at low pH. Two heterologous biosynthetic pathways have been expressed in <I>A. ferrooxidans</I> to produce either isobutyric acid or heptadecane from CO<SUB>2</SUB> and the oxidation of Fe<SUP>2+</SUP>. A sevenfold improvement in productivity of isobutyric acid was obtained through improved media formulations in batch cultures. Steady&#8208;state efficiencies were lower in continuous cultures, likely due to ferric inhibition. If coupled to solar panels, the photon&#8208;to&#8208;fuel efficiency of this proof&#8208;of&#8208;principle process approaches estimates for agriculture&#8208;derived biofuels. These efforts lay the foundation for the utilization of this organism in the exploitation of electrical energy for biochemical synthesis. Biotechnol. Bioeng. 2016;113: 189&ndash;197. &copy; 2015 Wiley Periodicals, Inc.</P>

2016

0006-3592

1097-0290

113

1

pp.189-197

10.1002/bit.25703

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART73815249

electrofuels; alkanes; isobutyric acid; isobutyraldehyde; metabolic engineering; biofuels