Molecular biology, a tool for bioprospection of plants secondary metabolism in Colombia

Plant secondary metabolites play an important role in plant-plant, plant-microorganisms and plant-insect interactions. They also protect the plants against stress environmental conditions. Plant secondary metabolites are also very important to humans due to their nutritional, pharmaceutical, medical and industrial properties. However, the secondary metabolism of tropical plant species still remains very poorly understood and characterised at the biochemical, molecular and genetic level. Within bioprospection programs to study the biodiversity of Colombian plants, the secondary metabolism is a very important target. Here we present an experimental methodology based on genomic DNA isolation from field collected plants, and the use of degenerate primers to PCR amplify genes that encodes pyridoxal-dependent enzymes which are involved in the alkaloids biosynthesis. Based on sequence homology we designed degenerate primers to amplify conserved gene sequences from 18 different plant families. Six putative tydc/tdc decarboxylases sequences were obtained from plants of the Piper genus. This report shows the usefulness of the DNA collection and PCR-based methodology e to increase the understanding and exploration of the secondary metabolism of Colombian plants. Key words: Bioprospection, secondary metabolism, degenerate primer, microarrays, PLP-dependent decarboxylases