Month: October 2024

Marine bacterial symbionts: Challenging evolutionary norms and informing conservation

Interactions between organisms, particularly in symbiotic relationships, are a key driver of biological innovation in marine ecosystems. My research leverages advanced sequencing technologies and bioinformatics to examine the dynamics of bacterial symbionts across diverse marine hosts, including sharks, anglerfish, and corals. This work elucidates the evolutionary trajectories and transmission mechanisms of symbiotic bacteria, revealing unique patterns that diverge from those observed in terrestrial symbioses. Furthermore, I investigate the influence of environmental factors on host-associated microbiomes, highlighting their critical role in host health and ecosystem functioning.

 

Dr. Lydia Baker

Assistant Professor, CSUMB

Dr. Lydia Baker earned their Ph.D. in Oceanography from the University of Hawai’i at Mānoa, focusing on diatom-associated bacteria. They completed postdoctoral research at Oregon State and Cornell, studying microbial interactions and symbiosis in anglerfish and coral respectively. Dr. Baker is currently an Assistant Professor at California State University Monterey Bay, where their research covers microbial ecology, symbiont evolution, and their impact on marine ecosystems.

Beyond Symbiosis: Reframing Of The UCYN-A Marine N2-fixing Partnership

Primary endosymbiosis is the biological process which led to the domestication of mitochondria and consequently the evolution of complex life on Earth. It is also responsible for the origin of the two photosynthetic organelles in eukaryotes which gave rise to land plants and many algal lineages. Research into marine microbes has revealed the fourth known occurrence of primary endosymbiosis which resulted in a novel N2-fixing organelle called the nitroplast. Candidatus Atelocyanobacterium thalassa, or UCYN-A, is a metabolically streamlined N2-fixing cyanobacterium previously reported to be an endosymbiont of a marine unicellular alga. Here we show that UCYN-A has been tightly integrated into algal cell architecture and organellar division and that it imports proteins encoded by the algal genome that expand its metabolic capabilities. For instance, UCYN-A biosynthetic pathways previously reported to be incomplete are restored by participation of nuclear-encoded proteins. The eukaryotic cell supports the process of N2-fixation with cytochrome P450 monooxygenases and flavodoxin electron-transfer proteins, and regulates UCYN-A circadian rhythm with cryptochromes. Furthermore, nuclear and nitroplast genomes together encode a vitamin B12 (adenosylcobalamin) biosynthetic pathway which may enable B. bigelowii to avoid B12 deficiency in the marine environment. This new perspective on a key player in the marine nitrogen cycle provides insight into the mechanisms of eukaryotic nitrogen fixation and the transition from symbiont to organelle.

 

Dr. Tyler Coale

Postdoctoral Researcher, UCSC

Dr. Tyler Coale is a postdoctoral researcher affiliated with UCSC and has previously studied the physiological response of phytoplankton in low iron conditions. Dr. Coale completed a B.S. in Plant Sciences at UCSC and went on to work as a technician in the field of chemical oceanography with Ken Bruland at UCSC and later with Kristen Buck at the Bermuda Institute of Ocean Sciences.

Shaping the Future of California Currents: Insights from Seasonal Forecasts to Climate Projections

The California Current Ecosystem (CCE) is a highly productive eastern boundary upwelling system, in which seasonal upwelling fuels primary production that supports a thriving marine ecosystem and socioeconomically valuable services including fisheries and tourism. The CCE and its resources are strongly driven by changes in the physical and biogeochemical environment, both of which experience considerable variability on timescales ranging from days to centuries. Prognostic information on this variability is therefore highly desirable for marine resource users, for example managers of fisheries whose target populations are sensitive to variations in the climate system. In this presentation, I will present a number of recent and ongoing efforts that have begun to explore the predictability and forecast skill of physical and biogeochemical properties in the CCE on seasonal-to-interannual (~1-24 months), decadal (~5- 20 years) and long-term (~50-100 years) timescales. I will also describe, when known, the physical mechanisms driving predictability in that range of timescales. Skillful forecasts and predictions of the physical and biogeochemical state in the CCE have the potential to provide actionable information to those managing the CC marine resources.

 

Dr. Mercedes Pozo Buil

Associate Project Scientist, UCSC/NOAA

Dr. Mercedes (Mer) Pozo Buil is a physical oceanographer interested in ocean modelling, climate change, ocean and climate dynamics, and decadal climate variability and its impact on marine ecosystems. She is an Associate Project Scientist at the University of California Santa Cruz in the Institute of Marine Sciences, working at the Ecosystem Science Division of the NOAA Southwest Fisheries Sciences Center in Monterey, California. Mer received two bachelor of science degrees in marine and environmental science, and a master’s degree in physical oceanography from the University of Cadiz in Spain. She holds a doctoral degree from the Georgia Institute of Technology.

Background

A collaborative sea otter study led by University of California, Santa Cruz, researchers is underway in Elkhorn Slough. Participating organizations and agencies include CDFW, USGS, Monterey Bay Aquarium, The Marine Mammal Center, ESNERR (ROMP), USFWS, and others. The purpose of the study is threefold: (1) to provide updated information on sea otter body condition, foraging success, and habitat use for comparison with data from a previous study conducted 2013–2016, (2) to provide novel information on sea otters’ physiological responses to stressors, and (3) to provide novel information on the social structure of sea otters. This fall, sea otter captures in Elkhorn Slough will occur for the third consecutive year. The goal is to recapture and resample sea otters tagged in previous years, replace missing tags, and capture new sea otters to add to the study. Sea otters will be captured primarily using tangle nets and transported to MLML Marine Operations for sedation, sampling, and tagging. After sampling and tagging are complete, the sedation will be reversed, and the sea otters will be transported back to their capture location and released. Monitoring of tagged sea otters is ongoing.