Active microbial communities in deeply buried sediments

Location: Baltic Sea Basin (IODP Expedition 347)

The Baltic Sea Basin is a eutrophic intercontinental sea that experiences seasonal hypoxia, high

sedimentation rates, and drastic salinity gradients. Over the last glaciation-deglaciation cycle,

variations in these attributes were recorded in the sediment, and changed the types of microbial

communities deposited in the sediment. We are using metatranscriptomics to examine the active

portion of the microbial communities in the basin's sediments, and connect the active processes

to the in situ geochemistry.

Antimicrobial gene expression in marine deep biosphere

Location: Mariana Forearc (IODP Expedition 366)

The marine deep subsurface biosphere has advanced our knowledge of early Earth processes,

carbon cycling, and microbe-mineral interactions, but the role antimicrobials have played in

competition and survival strategies is poorly understood. We are using metatranscriptomics to

analyze the active microbial community structure and function, as well as the diversity of

antimicrobial gene expression in subsurface sediment. This study is heavily focused on the

ecological roles that antimicrobials play within the marine deep biosphere. High-throughput

culturing from the deep subsurface biosphere. The goal of this project is to isolate and culture single

cells from the marine deep subsurface biosphere. Single cells from the sediment are isolated

using a BD FACSJazz and cultured using targeted media. Using 16S rRNA gene targets, the isolates a

re identified and growth conditions are further characterized.


Characterization of Deep Marine Subsurface Fungi from South Pacific Gyre Sediments

Location: South Pacific Gyre (IODP Expedition 329)

The South Pacific Gyre is known for some of the most nutrient and organic carbon replete

sediments in the world. Within the last decade, it has been shown that eukaryotes, such as fungi,

are thriving in these marine sediments. For this study, we are using both culture-dependent and

independent methods to characterize the fungal community and determine their role in 

biogeochemical cycling as well as their adaptation to harsh environments.


From Genomes to Ecosystems: A new look at carbon cycling within a wetland mangrove

Location: Mission-Aransas National Estuary Research Reserve

To determine the amount of methane emitted from wetlands, it is imperative that we first

accurately determine the process of methane production, consumption, and oxidation. Wetlands

may only cover a small fraction of Earthcoasts (0.5%), but they are a significant contributor to

coastal sediment carbon storage (10-15%) (Alongi, 2014).

Along the Texas coast, these ecosystems are expanding unchecked due to lack of annual freeze

s, replacing native salt marsh  habitat. The overall goal of this project is to better understand carbon

remineralization in a wetland mangrove ecosystem through molecular and geochemical analyses. This

project will evaluate carbon and sulfur cycling over a diurnal and seasonal timescale.