Methods and systems for producing products using engineered sulfur oxidizing bacteria

A system for producing isobutanol from genetically modified sulfur-oxidizing and iron-reducing bacteria (SOIRB) and iron oxidizing bacteria (IOB), said system comprising:

• a first bioreactor comprising sulfur-oxidizing and iron-reducing bacteria (SOIRB), wherein said SOIRB comprises a valine biosynthesis metabolic pathway that produces 2-keto acids and is genetically modified to include a 2-keto-acid decarboxylase gene and an alcohol dehydrogenase gene, said SOIRB being genetically modified so that said genes in said SOIRB convert said 2-keto acids to isobutanol;
• a first source of ferric iron in fluid communication with said first bioreactor;
• a first source of ferrous iron produced by said first bioreactor, said first bioreactor configured to feed said first source of ferrous iron to a second bioreactor, said second bioreactor comprising iron oxidizing bacteria (IOB), wherein said IOB comprises a valine biosynthesis metabolic pathway that produces 2-keto acids and is genetically modified to include a 2-keto-acid decarboxylase gene and an alcohol dehydrogenase gene, said IOB being genetically modified so that said genes in said IOB convert said 2-keto acids to isobutanol;
• and
• a second source of ferric iron produced by said second bioreactor, said second bioreactor configured to feed said second source of ferric iron to said first bioreactor.