Link between heterotrophic capacity of Red Sea coral holobiontsApply
Nitrogen availability is a key limiting factor for primary production on many coral reefs. As such, benthic organisms such as corals adapted and evolved efficient uptake and (re)cycling of the available nitrogen. The microbiome of coral holobionts aids in this cycling of nitrogen by 1) creating de novo bioavailable nitrogen via fixation of atmospheric dinitrogen (N2) performed by so called diazotrophs, and 2) alleviating bioavailable nitrogen through denitrification. While the latter seems counterintuitive at first, the majority of energy for coral holobionts is produced by a symbiotic relationship with photosynthetic dinoflagellates of the family Symbiodiniaceae which need to be in a nitrogen-limited state to translocate their photosynthates to the coral host. As such, denitrification could benefit coral holobiont health by aiding in keeping Symbiodiniaceae in a nitrogen-limited state. Furthermore, Tilstra (2020) hypothesized that, similar to N2 fixation, denitrification is linked to the heterotrophic capacity of the coral holobiont as the photosynthates translocated from the Symbiodiniaceae act as a food source for the mainly heterotrophic denitrifiers. As such, assessing nitrogen cycling pathways on corals with varying heterotrophic capacity (i.e., ranging from the autotrophic to the very heterotrophic end of the mixotrophic spectrum) can provide evidence for this hypothesis.
Program - Marine Science
Division - Biological and Environmental Sciences and Engineering
Faculty Lab Link - https://www.kaust.edu.sa/en/study/faculty/raquel-peixoto
Center Affiliation - Red Sea Research Center
Field of Study - Coral reef microbiology
Associate Professor, Marine Science
Prof. Peixoto's research has outlined the protocols and proved the concept that the manipulation of coral-associated microorganisms, using Beneficial Microorganisms for Corals (BMCs), is possible and can increase the host's resilience and resistance against environmental threats. This pioneering work has contributed to pave the way for new approaches to reveal and explore mechanisms of marine microbiology and symbiotic interactions. As a Beneficial Microbes for Marine Organisms network (BMMO) founder and chair, her goal is to keep promoting a powerful international platform where basic knowledge can be strengthened and transformed into products to be used for marine ecosystems and sustainable development, as part of her projects on coral reef protection, restoration and rehabilitation.
Desired Project Deliverables
One scientific publication.