During RP1&2 MARBLES has obtained 500+ new isolated from sponges, algae, and salmon skin. Protocols for the isolation of slow growing microbes and consortia have been developed. The microbial taxonomic biodiversity from these samples has been characterized by means of metagenomic analysis, 16S sequencing of the microbiomes as well as isolating the bacteria and testing different culture conditions which served as the basis to create the strain collections that became the building blocks of the project. Bioactive strains were funneled into the different tasks and work packages.
Panels of pathogens were selected to test microbiomes, microbial strains and bioactive compounds. Bioactive microbial single strains, co-culture and consortia have been identified, and the natural product BGCs and the molecules that could potentially be involved in the antagonism have been identified. A platform to screen simultaneously the chemical diversity in an extract together with its bioactivity is been used to pinpoint to possible novel bioactive compounds. Elicitors that activate cryptic BGCs have also been identified. Novel tools that integrate metabolomic, genomic and phenotypic data have been developed in order to dereplicate and prioritize samples and compounds.
The microbial library generation, the libraries of extracts and the high throughput screening (HTS) against panels of human, plant and fish pathogens has generated a lot of bioactivity data. Bioactivity, metabolomic, chemical and genetic information, including compound structure elucidation have produced several interesting candidates. All these datasets are being stored in a centralized database.
During the third reporting period, a method for testing fish pathogen inhibition by a complex microbial community (a microbiome) has also been developed. Microbial strains and consortia have also been selected and are undergoing trials to prove their plant protective effect against salinity and drought stress.
Metatranscriptomics was performed originally from sponges but a more sustainable approach for algae-bacteria has proved a better alternative as micro-algae are more suitable for smaller scale laboratory experiments. Metatranscriptomes were initially generated from mixed cultures of algae and bacteria, however, the algal transcripts were dominating the analyses. Therefore, the algal microbiome was enriched with respect to pathogen inhibitory properties and generated and analyzed for these setups, leading to the identification of BGCs of interest. A multiomics approach was also used to characterize the community composition, genetic potential, differential gene expression, and secondary metabolite production associated with inhibitory activity over a time-course of pathogen challenge.
Prioritization of interesting strains, along with their bioactive extracts, and the compounds associated to the bioactivity have been one of the main focus of the project during this period. Decision trees and criteria selection including bioactivity, genetic information, metabolomic and chemical data along with compound structure elucidation have been developed. The selection criteria together with input of the advisory boards: scientific and industrial experts have guided the selection of the bioactive candidates that are now undergoing scale up and further validation.
MARBLES continues with the great dissemination and communication strategy through the website and social media channels. 11 MARBLES publications have been published during RP3, bringing the total number of publications from the project to 17. In RP3, 95 dissemination and communication activities were recorded by partners with an estimated reach of 47,474 stakeholders including the scientific community, industry, policymakers, civil society, general public and media. MARBLES continues its participation together with the AIMS cluster (projects funded under the same FNR-11-2020 call) with podcasts, shared newsletters, seminars and the annual joint meeting.
MARBLES continues its commitment to comply with European regulations and to ensure the sustainable and environmental use of the marine resources as well as the use of any future natural products discovered. MARBLES has actively participated in several BBNJ events sessions and has published several policy briefs and one book titled “Decoding Marine Genetic Resource Governance Under the BBNJ Agreement” and holds regular meetings with the Advisory Panel of Policy and Legal Experts (APPLE) and the Panel of Industry Experts (PIE).
