Bacterial sphinogolipids as signaling molecules
We study a unique example of a eukaryotic-bacterial interaction in which diffusible signals from the prey bacteria Algoriphagus trigger the transition from single cells to colony development in the choanoflagellate Salpingoeca rosetta. Our goal is to elucidate the nature and function of the microbial signals that elicit morphogenic responses in choanoflagellates and how these signals impact the cell biology of other members of the microbial community. In collaboration with Christine Beemelmans (Max Plank Institute, Leibniz) and Dominic Campopiano (University of Edinburgh) and funded by the Victoria S. and Bradley L. Geist Foundation (PI: Alegado) and NSF IOS01558169 (PI: Alegado)
Bacterial basis of larval settlement
This effort will focus on questions relating to both bacterial cues that induce larvae to stop swimming, attach to a surface and undergo metamorphosis and larval response mechanisms, e.g., where on the larva does a bacterial “product” act to stimulate settlement, how is that signal perceived by a larva, and how does that stimulation result in the dramatic developmental events of metamorphosis? In collaboration with Mike Hadfield (Pacific Bioscience Research Center), Brian Nedved (PBRC), and Shugeng Cao (UH Hilo) and funded by the Gordon and Betty Moore Foundation.
Gut microbiota mediated bile acid alterations in hepatic carcinogenesis
Uncovering the molecular mechanisms that link metabolic disruptions in gut microbial host co-metabolism to metabolic disorders and liver cancer. Deciphering the complex metabolic interactions in the gut-liver-brain axis. Collaborating with Wei Jia (UH Cancer Research Center) and funded by the National Cancer Institute (PI: Jia; co-PI; Alegado)
Characterization of large-scale 16S rRNA gene libraries from stations in Heʻeia Coastal Oceans Observing System located in Heʻeia Fishpond. We are investigating the drivers of this diversity with a specific focus on microbial responses to disturbance and stressors including storm events. In collaboration with Paepae o Heʻeia, Margaret McManus, Kathleen Ruttenberg, Kiana Frank and Brian Glazer at UH Mānoa (Na Kilo Honua o Heʻeia). Funded by NOAA Sea Grant (PI: Alegado) and the USGS State Water Resources Resource Institute Program (PI: Alegado)
Microbial Responses to Land-based Sources of Pollution
Land-based sources of pollution (LBSP) drive coastal algal blooms, leading negative ecological and economic impacts, and are often exacerbated by declines in grazers or loss of habitat. Our goal is to identify areas vulnerable to blooms using American Samoa as comparison for on-going studies of the Main Hawaiian Islands. We selected coastal sites spanning a human use gradient ranging from pristine (no residents within the watershed, little LBSP, few obstructions to water movement and sparse run-off) to heavily impacted (downstream of dense residential areas with substantial sediment loads and slowed water movement) – pre-conditions for an algal bloom. Sampling surface water for inorganic nutrients, ∂15N, and planktonic microbial community, tissues of indicator algae and characterization of the benthic community. In collaboration with Celia Smith (UH Manoa, Botany) and funded by the USGS Water Resources Resource Institute Program.
Kilo Lani: Observations of Climate Patterns in Historical Hawaiʻi
Our long-term goal is to use indigenous-based historical records to reconstruct Hawaiian regional climate beyond conventional instrument records. We employ 2 complementary strategies to develop a deeper understanding of how climate modes, such as ENSO, affected regional climates in Hawai’i: introducing additional historical observations through Hawaiian language newspapers and developing climate indicators specific to Hawai’i using introduced and native tree species. This project is a collaboration with Axel Timmermann (Oceanography/Interactional Pacific Research Center) and Puakea Nogelmeier (Kawaihuelani Center for Hawaiian Language). Funded by the NOAA Joint Institute for Marine and Atmospheric Research and the USGS Pacific Island Climate Science Center (PI: Alegado)