Copyright (c) 2015 AJC
This work is licensed under a Creative Commons Attribution 4.0 International License.
Acetyl-CoA Pathway for Biosynthesis of Organics: A Review
Corresponding Author(s) : Gugan Jabeen
Asian Journal of Chemistry,
Vol. 27 No. 1 (2015): Vol 27 Issue 1
Abstract
A great diversity of microorganisms have tendency to reduce numerous organic compounds and gases. Various acetogens have potential to produce valuable organic compounds by acquiring environmentally sustainable approaches. Acetogens like Sporomusa ovata, Clostridium ljungdahlii, Clostridium aceticum, Moorella thermoacetica and Acetobacterium woodii are attractive species for fixing waste greenhouse gases. Acetogens utilize acetyl Co-A pathway for acetate production with small amount of butanol and alcohols. Genetic mutations, metabolic engineering and bioelectrochemical synthesis can be adopted to divert the chemical reaction pathway apart from acetate production. In bioelectrochemical synthesis, electrodes material, electrodes surface areas, kind of biofilms, ion exchange membranes, internal resistances, etc. effect electron exchange between microorganisms and electron acceptors. Adapted strains provide an insight into the mechanisms of extracellular electron exchange. There's a requirement to modify the metabolic pathways of microorganisms by sequencing their genomes to obtain ethanol, isopropanol, n-butanol, etc. This review provides insight of natural and engineered methods for scavenging greenhouse gases using acetyl Co-A metabolic pathways adopted by acetogens. The unique approach is the critical discussion leading to the selection of acetyl Co-A pathway on the basis of its energy efficiency. The research on bioelectrochemical process, metabolic engineering and their applications are being focused to give a comprehensive review on the subject.
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References
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H.-X. Jin, Z.-Q. Liu, Z.-C. Hu and Y.-G. Zheng, Biochem. Eng. J., 74, 1 (2013).
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W.H. Ramos-Vera, V. Labont'e, M. Weiss, J. Pauly and G. Fuchs, J. Bacteriol., 192, 5329 (2010).
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T.I. Doukov, Science, 298, 567 (2002).
S.W. Ragsdale and M. Kumar, Chem. Rev., 96, 2515 (1996).
V. Müller, Appl. Environ. Microbiol., 69, 6345 (2003).
S. Schmidt, E. Biegel and V. Müller, Biochim. Biophys. Acta Bioenerget.,1787, 691 (2009).
S.T. Yamamoto and S.M. Liu, J. Biol. Chem., 258, 1826 (1983).
S.W. Ragsdale, J.E. Clark, L.G. Ljungdahl, L.L. Lundie and H.L. Drake, J. Biol. Chem., 258, 2364 (1983).
S.I. Hu, E. Pezacka and H.G. Wood, J. Biol. Chem., 259, 8892 (1984).
L. Boynton, G.N. Bennett and F.B. Rudolph, Appl. Environ. Microbiol., 60, 2758 (1996).
J.P. Nakas, M. Schaedle, C.M. Parkinson, C.L.E. Coonley and S.W. Tanenbaum, Appl. Environ. Microbiol., 6, 6 (1983).
H. Biebl, J. Ind. Microbiol. Biotechnol., 27, 18 (2001).
K. Leja, K. Czaczyk and K. Myszka, Afr. J. Biotechnol., 10, 11093 (2011).
S. Papanikolaou, M. Fick and G. Aggelis, J. Chem. Technol. Biotechnol., 79, 1189 (2004).
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Y.L. Lin and H.P. Blaschek, Appl. Environ. Microbiol., 45, 966 (1983).
R. Kalscheuer, T. Stolting and A. Steinbuchel, Micobiol., 152, 2529 (2006).
S.T. Withers, S.S. Gottlieb, B. Lieu, J.D. Newman and J.D. Keasling, Appl. Environ. Microbiol., 73, 6277 (2007).
J.S. Chen and S.F. Hiu, Biotechnol. Lett., 8, 371 (1986).
L.L. Bermejo, N.E. Welker and E.T. Papoutsakis, Appl. Environ. Microbiol., 64, 1079 (1998).
M. Peretz, O. Bogin, S. Tel-Or, A. Cohen, G. Li, J.S. Chen and Y. Burstein, Anaerobe, 3, 259 (1997).
G.R. Duncombe and F.E. Frerman, Arch. Biochem. Biophys., 176, 159 (1976).
L.S. Jenkins and W.D. Nunn, J. Bacteriol., 169, 42 (1987).
A.A. Ismaiel, C.X. Zhu, G.D. Colby and J.S. Chen, J. Bacteriol., 175, 5097 (1993).
R.J. Lamed and J.G. Zeikus, Biochem. J., 195, 183 (1981).
S. Atsumi and J.C. Liao, Curr. Opin. Biotechnol., 19, 414 (2008).
D.F. Becker, J.A. Fuchs, D.K. Banfield, W.D. Funk, R.T. MacGillivray and M.T. Stankovich, Biochemistry, 32, 10736 (1993).
H. O'Neill, S.G. Mayhew and G. Butler, J. Biol. Chem., 273, 21015 (1998).
K.K. Wallace, Z.Y. Bao, H. Dai, R. Digate, G. Schuler, M.K. Speedie and K.A. Reynolds, Eur. J. Biochem., 233, 954 (2010).
B.M. Ennis and I.S. Maddox, Biotechnol. Lett., 7, 601 (1985).
M. Kopke, C. Held, S. Hujer, H. Liesegang, A. Wiezer, A. Wollherr, A. Ehrenreich, W. Liebl, G. Gottschalk and P. Durre, Proc. Natl. Acad. Sci. USA, 107, 13087 (2010).
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V. Muller and G. Gottschalk, in eds.: H.L. Drake,The Sodium Ion Cycle in Acetogenic and Methanogenic Bacteria: Generation and Utilization of a Primary Electrochemical Sodium Ion Gradient, In: Acetogenesis, Chapman & Hall, New York, pp. 127-156 (2011).
N. Qureshi, A. Lolas and H.P. Blaschek, J. Ind. Microbiol. Biotechnol., 26, 290 (2001).