Project Title

Collaborative Research: Diving Into the Ecology of an Antarctic Ascidian Microbiome-Palmerolide Association Using a Multiomic and Functional Approach

Summary

Event Number:
B-018-N
NSF / OPP Award 2142912

Program Director:
Dr. William Ambrose

ASC POC/Implementer:
Kenneth Vicknair / Jamee Johnson

Principal Investigator(s)

Dr. Alison Murray
alison@dri.edu
Desert Research Institute
Earth and Ecosystem Sciences
Reno, Nevada

Location

Supporting Stations: RV/IB Nathaniel B. Palmer
Research Locations: Western Antarctic Peninsula

Description

This project studies an emerging biosynthetic system from a polar ascidian (Synoicum adareanum)-microbe association that produces palmerolide A (palA), a natural product with activity against the proton-pumping enzyme V-type H+-ATPase (VHA). The objectives include (1) determining the microbiome composition, metabolome complexity, palA levels, and mitochondrial DNA sequence of S. adareanum morphotypes at sites in the Antarctic Peninsula; (2) characterizing the Synoicum microbiome using a multiomics strategy; (3) assessing the potential for co-occurrence of the microbe Candidatus Synoicihabitans palmerolidicus -palA-VHA in host tissues; and (iv) exploring the role of palA in modulating VHA activity in vivo and its effects on ascidian-microbe ecophysiology. The project results will inform the geospatial distribution, cellular localization, ecological and physiological roles of this intimate host-microbial association in which the ascidian host bioaccumulates VHA-inhibiting palA. Likewise, a knowledge base of microbial processes in this multispecies core microbiome and of the pal biosynthetic gene cluster as it interacts with its antarctic ascidian host will be developed. In addition to elucidating the ecophysiological roles of palA in their native ascidian-microbe association, the results will contribute to the success of translational science, which aligns with the National Science Foundation’s interests in promoting basic research that leads to advances in biotechnology and bioeconomy.

Field Season Overview

A team of up to 17 participants plans to deploy for a research cruise in 2025-26, potentially from a University-National Oceanographic Laboratory System (UNOLS) vessel departing Punta Arenas, Chile. The principal investigators and project participants plan to collect S. adareanum morphotypes by scuba dives and bottom trawls. Up to two scuba dives consisting of a buddy pair will be conducted per day. Dive operations will be conducted primarily from small boats, though other small boats may be utilized if deemed appropriate given local conditions. Before starting dive operations, a separate team may conduct remotely operated vehicle (ROV) reconnaissance missions to evaluate potential dive sites. Final decisions on small boat operations and the number and timing of small boats in the water will be confirmed with the vessel captain and crew. Sampling will take place in the South Shetland Islands, the Palmer Archipelago, the Wilhelm Archipelago, and off the Danco Coast. Conductivity, temperature, depth (CTD) rosette casts will be done in the vicinity of dive and trawl locations to collect water samples and record oceanographic data.

Deploying Team Members