The puzzle of the Krebs citric acid cycle: Assembling the pieces of chemically feasible reactions, and opportunism in the design of metabolic pathways during evolution

@article{MelndezHevia2006ThePO,
  title={The puzzle of the Krebs citric acid cycle: Assembling the pieces of chemically feasible reactions, and opportunism in the design of metabolic pathways during evolution},
  author={Enrique Mel{\'e}ndez-Hevia and Thomas G. Waddell and Marta Cascante},
  journal={Journal of Molecular Evolution},
  year={2006},
  volume={43},
  pages={293-303}
}
The evolutionary origin of the Krebs citric acid cycle has been for a long time a model case in the understanding of the origin and evolution of metabolic pathways: How can the emergence of such a complex pathway be explained. [] Key Method We have analyzed the Krebs cycle as a problem of chemical design to oxidize acetate yielding reduction equivalents to the respiratory chain to make ATP. Our analysis demonstrates that although there are several different chemical solutions to this problem, the design of…
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