SingLaby:Investigating Labyrinthulomycetes parasitism in Singapore marine ecosystems (MOE AcRF Tier 1)

• Funding: Ministry of Education - Academic Research Fund (AcRF) Tier 1 – Singapore
• Role: Principal Investigator
• Period: 2022-2025

Labyrinthulomycetes are ubiquitous protists (microbial eukaryotes) present in marine and estuarine environments. They are found as free living cells or in association with organic detritus. Since the discovery of Labyrinthulomycetes, advances in the understanding of this group include their phylogenetic reclassification within the protist lineage Stramenopiles (they were originally classified as Fungi) and mounting evidence of their role as opportunistic parasites of clams, juvenile abalone and seagrasses . Although Labyrinthulomycetes were described as the etiologic agent of seagrass wasting disease (a malady that destroyed meadows of the eelgrass Zostera marina along the Atlantic coasts of North America and Northern Europe in the 1930s) almost 90 years ago, it is still unclear whether the conditions that promote this pathology rely on plant health and defense capabilities or the virulence of Labyrinthula species and haplotypes, or a combination of host and pathogen characteristics, especially in other seagrass species for which very little information is available. Studies from coastal waters of China, Japan and USA have shown that Labyrinthulomycetes communities can change across seasons and habitats, even though the key environmental drivers structuring their community remain unclear. Despite the growing human pressure on the coastal waters of Singapore, as well as the growing interest in its critical ecosystem services, such as sequestering and storing ”blue” carbon in seagrass meadows, studies on opportunistic parasites are still scarce, particularly for Labyrinthulomycetes, for which there is a paucity of information in tropical and equatorial waters. The limited knowledge on the community structure and dynamics of Labyrinthulomycetes pathogenicity in equatorial marine ecosystems, combined with the observation of Labyrinthulomycetes sequences from our previous studies from Singapore waters, are the main motivations behind this proposal.