Evolution of the secondary metabolite versus evolution of the species

Abstract

Four stereochemical series of diastereomeric polyhalogenated chamigrane sesquiterpenes-headed by obtusol, isoobtusol, rogiolol, and cartilagineol-suggest the existence of four lineages of red seaweeds in the genus Laurencia. On another front, concerning marine ciliates, euplotane sesquiterpenes characterize worldwide the morphospecies Euplotes crassus, well differentiated from Euplotes raikovi, Euplotes rariseta, and Euplotes vannus, which furnish different-skeleton sesquiterpenoids, and the latter also C 30 -backbone isoprenoids. The latter three morphospecies, however, show polymorphism in the variability of their isoprenoids.Unarguably, the modern construction of phylogenetic trees and evolutionary events concerning species is based on molecules that are found in all organisms, such as rRNA coding fractions and highly conserved proteins for long distances, or polymorphic enzymes for population structure and dynamics. However, the correlation between gene and protein expression is low, and that between proteins and secondary metabolites is even lower, which throws much shadow on "lower" species that compete for space and resources, or defend themselves from predators, largely thanks to secondary metabolites. These often constitute their best taxonomic and phylogenetic markers. In this regard, biologists and natural products chemists live largely in separate, artificial worlds-the evolutionary biologist snubbing the secondary metabolite, and the chemotaxonomy of the natural products chemist providing little trait d'union, as it is typically concerned with gross comparisons of identities or similarities in molecular structures that ignore deep-seated chemical features.An example of gross structural comparison concerns a nominal species of red seaweed, Laurencia microcladia Kützing, 1865, of Atlantic origin although rather common in infralittoral areas of the Mediterranean (Fig. 1). The story begins with a sample of this seaweed from Cap Ferrat, along the Côte d'Azur, giving new polyhalogenated C 15 acetogenins, a class of compounds unique to seaweeds in the genus Laurencia and opisthobranch mollusks that feed on them. In this case, these are of the most com-*Lecture presented at

Analysis of metabolomic PCA data using tree diagrams

“…Clearly, the range and quantity of metabolites observed are dependent on both the organism’s proteome and genome, but direct correlations between gene expressions and the metabolome is low [19]. Nevertheless, metabolites have been associated with species evolution [20] and have been used to differentiate between different fungal species [21], different Escherichia coli species [22], and to monitor the adaptive evolution of yeast [23]. Phylogenetic trees have also been generated from the analysis of metabolic networks [24] and reproduce phylogenetic relationships between species derived from 16sRNA sequences [25].…”

Chemical Diversity and Biological Properties of Secondary Metabolites from Sea Hares of Aplysia Genus

“…Moreover, it is able to decrease the release of eicosanoids, with stronger potency on the cyclooxygenase (COX) pathway [ 120 ]. In 2014, Palaniveloo and Vairappan [ 20 ] studied the chemical relationship between red algae from the genus Laurencia and A. dactylomela from different geographical areas, having found a big diversity of chamigrenes, including rogiolol ( 83 ) which had been previously isolated from a Laurencia species [ 121 ]. Another study, involving two color variants of A. dactylomela , led to the isolation of nidificene ( 84 ) [ 122 ].…”

What is metabolomics all about?

“…The suite of secondary metabolites in an organism can be astonishingly complex, and while certain compounds may be found in different organisms, a vast number of compounds are very species-specific. Secondary metabolites are therefore considered as potential markers for taxonomy and phylogenetics (10). …”