In silico characterization of putrescine N-methyltransferase in Solanaceae species
The Solanaceae family comprises about 100 genera and 2,500 species, with a cosmopolitan distribution and greatest diversity in the Neotropical region. In Brazil, 36 genera and 506 species have been identified, including 236 endemic species. The family has a high diversity of species of economic importance as a source of food, medicinal extracts, and for ornamental use. The species are sources of bioactive secondary metabolites, with diverse applications. We made ae structural and functional characterization and developed three-dimensional models of putrescine N-methyltransferase (PMT) proteins, a key enzyme of secondary metabolism, involved in biosynthesis of nicotine, tropane alkaloids, and calistegines. We examined 48 PMT sequences from Solanaceae species available in public databases. A hydrophilic characteristic of PMT was found for all species, and the isoelectric point demonstrated a somewhat acidic character (5.4 - 6.6). We identified four functional domains in the PMT sequences. Cluster analysis by Neighbor-Joining was consistent with recent taxonomic classifications of the species.