Autopoietic symbiogenesis in secondary metabolism

The holobiont is a biological system made up of the host and its symbionts. These symbionts live in constant exchange of information and genetic material with the host, which configures a metabolome and a hologenome that is in adaptation and persistence. In this order of ideas arises the chemical evolution of the secondary metabolism through the symbiotic interactions and the modulation of the gene expression of the enzymes that control the biosynthetic pathways of the organisms involved; this is how the coevolution of the species determines the chemical and biosynthetic characteristics of the holobiont in terms of its response to environmental factors. Likewise, secondary metabolism as a molecular communicator in symbiosis also regulates the epigenetic mechanisms of gene expression to direct the response of the biological system to environmental stimuli. All this makes the secondary metabolites a fundamental part in the homeostatic balance of the holobiont and has allowed its evolution and speciation; it also configures the networks of chemical signals within a metabolic context of search for nutrients and defense of space, this increases the biological system in complexity and acquisition of fitness. The objective of this chapter is to analyze the role of secondary metabolites in the symbiosis, evolution, and participation of the holobiont as a metaorganism, which opens a new evolutionary paradigm in medicine toward the search for ecosystem equilibrium as a health-disease model.