Insights into genetic and biosynthetic diversity of cyanobacteria through multi-omics analyses
Year: 2021
Type: dissertation
Abstract: Cyanobacteria are one of the largest and most diverse groups of prokaryotes, and the only prokaryotes capable of oxygenic photosynthesis. They inhabit a wide variety of aquatic and terrestrial light-exposed environments, where they are key players in carbon and nitrogen cycles. These organisms show vast morphological and physiological diversity, and can achieve high densities under optimal conditions due to several adaptive strategies. Such mass-accumulation events are also known as cyanobacterial blooms. One of the major concerns involving cyanobacterial blooms is the production of potent toxins that can not only negatively affect the growth of phyto/zooplankton, but are also toxic to domestic and wild animals. Aside from toxins, cyanobacteria are known for producing a wide range of natural products, i.e., compounds with unique structure and biological activities, which can have applications in medicine and biotechnology, such as antibiotics, anticancer agents, polymers, and surfactants. The enzymes involved in the biosynthesis of cyanobacterial natural products are typically encoded in contiguous stretches of genomic DNA, known as biosynthetic gene clusters. These natural product biosynthetic gene clusters have been widely explored using genome mining approaches. However, other omics tools can considerably assist the study of biosynthetic pathways and improve predictions of the chemical structures of the compounds they encode. Despite the increasing number of new genomes and described natural products, cyanobacteria remain underexplored relative to other bacteria phyla. Thus, the aim of this thesis is to expand the knowledge on genetic diversity and the natural product biosynthetic potential of cyanobacteria using multi-omic approaches. Specifically, the distribution of natural product biosynthetic gene clusters from 184 publicly available genomes from the entire phylum were first mapped, and environmental adaptations and natural products from two toxic bloom-forming genera were explored in depth. In addition, diverse cyanobacteria from Brazilian biomes were screened for antimicrobial and anticancer activity. Overall, this thesis showed that combined omic approaches are capable of providing critical insights into the genetic and biosynthetic diversity of cyanobacteria. The results advance our understanding of how natural product biosynthetic gene clusters move among cyanobacterial genomes, and how environmental factors are related to toxin production, and also identified cyanobacteria that are the source of novel natural products. This knowledge is important in preventing damage caused by toxic bloom-forming cyanobacteria, and in the discovery of novel natural products with economic interest.
Source: Työväentutkimus Vuosikirja
Author: Popin, Rafael Vicentini
Language: English
Subfield: Applied Microbiology and Biotechnology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7066502689