Metabolism evolution

Ornston LN, W-K Yeh (1982) Recurring themes and repeated sequences in metabolic evolution. In Biodegradation and Detoxification of Environmental Pollutants (Ed AM Chakrabarty), pp. 105-126. CRC Press Inc, Boca Raton. 

In the course of this chapter devoted to the alkaloids of Pauridiantha, their biosynthesis has been mentioned and some chemotaxonomic correlations have been proposed. As all glucoalkaloids described here derive from strictosidine, a more systematic analysis of its metabolic evolution in plants seems of interest. 

I. S. Kulaev and K. G. Skryabin (1971). Reactions of abiogenic transphosphorylation involving high-polymer polyphosphates and their role in the phosphorus metabolism evolution. In Abstracts of the Symposium on Origin of Life and Evolutionary Biochemisty, Varna, Bulgaria, p. 22. 

In the course of early evolution, the metabolism becomes more and more integrated and centralized, so much so that a chemical conversion of highly integrated constituents tends to weaken the metabolism. The more central the constituent, the more severe is this effect of metabolic decay by chemical conversions, which leads us to yet another strategy of metabolic evolution the strategy of dual feedback. 

According to a general rule of organic chemistry, reactions involving the smallest molecules are catalytically the most restrictive. This rule holds notably for the build-up of carbon skeletons with the arithmetic Cl -F Cl = C2 (e.g., C2 = glycine or acetyl thioester). Therefore, it may not come as a surprise that in the course of metabolic evolution, these most simple carbon fixation reactions may fall by the wayside. Under these conditions, an autotrophic carbon fixation metabolism can only be maintained by a metabolic cycle, which multiplies the C2 unit autocatalytically in the absence of its de novo synthesis. A prominent example is the reductive citric acid cycle (C2 -F Cl... 

With regard to the discussion here, it is very important to grasp the importance of LGT, and discuss the evolution of metabohsm apart from the evolution of bacterial species, and perhaps apart from bacterial systematics altogether. Eventually, these two discussions may reunite, but for now the discussion of metabolic evolution is probably better done independently. 

Nisbet, E. G. Fowler, C. M. R 1999. Archaean metabolic evolution of microbial mats. Proceedings of the Royal Society of London, Series B, 266, 2375-2382. 

Cunchillos, C. and Lecointre, G. (2002). Early steps of metabolism evolution inferred by cladistic analysis of amino acid catabolic pathways. Comptes Rendus Biologies. 325, 119-29. 

Jantama, K. et al (2008) Combining metabolic engineering and metabolic evolution to develop nonrecombinant strains of Escherichia coli C that produce succinate and malate. Biotechnol Bioeng, 99, 1140-1153. 

Zhang, X. et al (2009) Metabolic evolution of energy-conserving pathways for succinate production in Escherichia coli. Proc. Natl. Acad. Scl U.S.A., 106, 20180-20185. 

Falkowsky, P.G. (2006). Tracing oxygen s imprint on earth metabolic evolution. Science 311 1724-1725. 

Nisbet EG, Fowler GMR Archaean metabolic evolution of microbial mate. Proc RSoc Lond B Biol Sci 1999, 266(l436) 2375-2382. 

The use of evolution to improve tolerance with the goal of also improving production has also been widely adopted by the metabolic engineering community, though with mixed results. In some cases, increased tolerance is associated with improved production. For example, the metabolic evolution of E. coli for fatty acid tolerance resulted in improved fatty acid production [125]. Evolution of non-transgenic, ethanologenic E. coli KCOl for increased ethanol tolerance resulted in improved production [126], similar to the observed outcome with evolution of KOll for ethanol tolerance to produce strain LYOl. 

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