Features of Diversity of Polyketide Synthase Genes in the Community of Freshwater Sponge Baikalospongia fungiformis
O. V. Kaluzhnaya, В. Б. Ицкович
Abstract
Abstract In the present study, we analyze the sequences of gene fragments of polyketide synthases (PKS) of microorganisms associated with the endemic Baikal sponge Baikalospongia fungiformis. PKSs are multienzyme complexes responsible for the synthesis of low molecular weight biologically active substances (BAS). Cloning and sequencing of the amplification products of the ketosynthase (KS) domain of PKS in the B. fungiformis microbiome reveal 18 unique sequences, most of which were highly identical (97–99%) to the genes of PKS of microorganisms from communities of other species of Baikal sponges. On phylogenetic trees, these groups of sequences form characteristic “Baikal clades.” Apparently, the basic sponge community that formed during the coevolution contains common groups of microorganisms that are potential producers of biologically active substances. BlastX analysis showed that the obtained fragments belong to bacterial polyketide synthases (phyla Cyanobacteria, Proteobacteria, Planctomycetes, Latescibacteria, and Gemmatimonadates), as well as eukaryotic algae (divisions Haptophyta and Ochrophyta). This work indicates a significant biotechnological potential of freshwater sponge communities and the prospects for research in the direction of searching for new natural metabolites in complex freshwater microbiomes.