Symbiotic Associations: Key Factors That Determine Physiology and Lipid Accumulation in Oleaginous Microorganisms

Abstract

Symbiosis naturally provides an opportunity for microorganisms to live together by mutual or one-way benefit. In symbiotic relationships, the microorganisms usually overcome the limitations of being free-living. Understanding the symbiotic relationships of oleaginous microorganisms provides potential route for the sustainable production of microbial-based alternative fuels. So far, several studies have been conducted in oleaginous microorganisms for the production of alternative fuels. However, some oleaginous microorganisms require high quantity of nutrients for their growth, and high level of energy and chemicals for harvest and separation of lipid bodies. Symbiotic associations can successfully be applied to address these issues. Of symbiotic associations, lichens and selective species of oleaginous endosymbiotic mucoromycotina have received substantial interest as better models to study the evolutionary relationships as well as single-cell oil production. Construction of artificial lichen system composed of cyanobacteria and oleaginous yeast has been achieved for sustainable production of lipids with minimum energy demand. Recently, endosymbiotic mucoromycotina species have been recognized as potential sources for biofuels. Studies found that endohyphal bacterium influences lipid profiling in endosymbiotic mucoromycotina species. Studies on the genetic factors related to oleaginous characteristics of endosymbiotic mucoromycotina species are scarce. In this regard, this review summarizes the different forms of symbiotic associations of oleaginous microorganisms and how symbiotic relationships are impacting the lipid formation in microorganisms. Further, the review also highlights the importance of evolutionary relationships and benefits of co-culturing (artificial symbiosis) approaches for sustainable production of biofuels.

Label-free third harmonic generation imaging and quantification of lipid droplets in live filamentous fungi

“…It is known that organic molecules sent from plant to fungi are lipids 79 , 80 , and that lipid droplets form in large amounts in hypha adjacent to the area of contact with the plant 81 . Similar to Phycomyces , arbuscular mycorrhizal fungi can accumulate significant amount of acquired organic carbon in the form of lipid droplets 82 . THG imaging of LDs as described here is a method that could be directly applied to living mycorrhizal fungi related to Phycomyces , without the need for any modification of the protocol, or other staining.…”

Perspectives on Converting Keratin-Containing Wastes Into Biofertilizers for Sustainable Agriculture

“…Due to the association of this type of organisms with plants, potential challenges may occur during the preparation or storage of the biofertilizers. Other bacteria whose growth and living are not relying on the plants such as free-living nitrogen-fixing bacteria are of great interest in keratin-derived biofertilizers (Lucy et al, 2004;Deka et al, 2020). The organisms used in keratin degradation have different mechanisms of action from those applied in biofertilizers (Korniłłowicz-Kowalska and Bohacz, 2011;Ortiz and Sansinenea, 2021;Sypka et al, 2021).…”

“…Due to the association of this type of organisms with plants, potential challenges may occur during the preparation or storage of the biofertilizers. Other bacteria whose growth and living are not relying on the plants such as free-living nitrogen-fixing bacteria are of great interest in keratin-derived biofertilizers (Lucy et al, 2004 ; Deka et al, 2020 ).…”