Perspectives!

With the valuable collaboration of the team iGEM-Alberta 2008, we linked the light-oxygen dependent regulation systems with the butanol production pathway and its electron-transfer-flavoprotein alpha and betha polypeptides, these constructs were donated by Dr. Douglas Ridgway.
(Reference: https://2008.igem.org/Team:The_University_of_Alberta/Butanerd)

Clostridium acetobutylicum is an anaerobic, spore-forming bacterium with the ability to ferment starch and sugars into solvents. In the past, it has been used for industrial production of acetone and butanol, until cheap crude oil rendered petrochemical synthesis more economically feasible. Both economic and environmental aspects have caused the pendulum to swing back again. Molecular biology has allowed a detailed understanding of genes and enzymes, required for solventogenesis.(1) Taking advantage of the metabolic versatility of R. sphearoides and R. palustris and their ability to fix Carbon dioxide, we aim to introduce the following constructions into these both bacteria so that the fixed carbon dioxide becomes into butanol.

We constructed the following circuits:

(A) The regulation part of the Repressor/Antirepressor system linked with the ETFA (electron- transfer-flavoprotein, alpha polypeptide) and the ETFB (electron-transfer-flavoprotein, beta polypeptide) (ETFA/B).

(B) This biobrick is the production part of the complete Repressor/Antirepressor system, consists in the PpsR dependent promoter sequence liked with the butanol production pathway.

(C) The regulation part of the two component system PrrABC linked with ETFA/B.

(D) This biobrick is the production part of the complete Two component PrrABC system, consists in the PrrA dependent promoter sequence liked with the butanol production pathway.

(E) The PrrABC-ETFA/B system linked with the PrrA dependent promoter and the butanol production pathway.

We have to clone these constructions into the pRK415 vector, and conjugate R. sphearoides and R. palutris, to finally test our system and the butanol production.

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References
1.- Ann N Y Acad ‘Sci., Dürre P., Fermentative butanol production: bulk chemical and biofuel. (2008) Mar;1125:353-62.
2.- Cong T. Trinh, Elucidating and reprogramming Escherichia coli metabolisms for obligate anaerobic n-butanol and isobutanol production Appl Microbiol Biotechnol DOI 10.1007/s00253-012- 4197-7
3.- Masayuki Inui & Masako Suda & Sakurako Kimura & Kaori Yasuda & Hiroaki Suzuki & Hiroshi Toda & Shogo Yamamoto & Shohei Okino & Nobuaki Suzuki & Hideaki Yukawa Expression of Clostridium acetobutylicum butanol synthetic genes in Escherichia coli Appl Microbiol Biotechnol (2008) 77:1305–1316
4.- Wolfram Andersch, Hubert Bahl, and Gerhard Gottschalk Level of Enzymes Involved in Acetate, Butyrate, Acetone and Butanol Formation by Clostridium acetobutylicum Eur J Appl Microbiol Biotechnol (1983) 18:327-332
5.- Hubert Bahl, Wolfram Andersch, and Gerhard Gottschalk, Continuous Production of Acetone and Butanol by Clostridium acetobutylicum in a Two-Stage Phosphate Limited Chemostat European J Appl Microbiol Biotechnol (1982) 15:201-205