Sulfur is an essential element to life; a terminal electron acceptor in anaerobic respiration and structural components to many important biomolecules. Sulfur metabolic pathways evolved millions of years ago, and can leave geochemical signatures in the rock record, yet are still very important today. Our lab researches several aspects of S cycling:
1.) Sulfur metabolism & symbiosis (both terrestrial and marine plants)
2.) Veracity of geochemical S signatures in ancient marine sediments
3.) Macroalgae biomass deconstruction
1.) Sulfur metabolism & symbiosis (both terrestrial and marine plants)
2.) Veracity of geochemical S signatures in ancient marine sediments
3.) Macroalgae biomass deconstruction
S Symbiosis in Seagrass
Environmental processes can lead to the accumulation of hydrogen sulfide in various habitats. Although hydrogen sulfide is toxic at high concentrations, many plants and animals have evolved adaptations to tolerate it, often through symbiosis with specific microbes.
Environmental processes can lead to the accumulation of hydrogen sulfide in various habitats. Although hydrogen sulfide is toxic at high concentrations, many plants and animals have evolved adaptations to tolerate it, often through symbiosis with specific microbes.
Seagrasses play a crucial role in protecting coastlines in shallow marine environments across the globe. These settings often experience elevated sediment sulfide levels. Seagrass ecosystems are also important blue carbon sinks. However, climate change may alter hydrogen sulfide levels in these shallow marine systems, potentially leading to toxicity and loss of seagrass meadows. Understanding how the environmental microbiome associated with seagrasses can enhance sulfide tolerance is critical for preserving these vital ecosystems. Research into this symbiotic relationship could offer insights into improving seagrass resilience in the face of changing environmental conditions.
We use S K-edge XRF and XAS to study evidence of sulfide intrusion in various stages of developed roots and rhizomes of seagrasses from California (and to be extended to Puerto Rico). This research is in collaboration with Roger Bryant (Purdue University).
Geochemical S Signals
Our understanding of oxygen concentration in the atmosphere over time is based on geochemical measurements of redox sensitive elements. Sulfur is present in the rock record as both a reduced form, as pyrite, and oxidized form, sulfate. However, measurements of sulfate are typically obtained from carbonate associated sulfate (CAS), where the assumption is that seawater sulfate passively incorporates into carbonate minerals as they precipitate. Through our research, we have found that there are more controls on CAS than was previously assumed, and that oxidized sulfide minerals can result in a false CAS signature. Synchrotron XRF is essential for identifying the sources of sulfur signatures in ancient marine sediments.
Our understanding of oxygen concentration in the atmosphere over time is based on geochemical measurements of redox sensitive elements. Sulfur is present in the rock record as both a reduced form, as pyrite, and oxidized form, sulfate. However, measurements of sulfate are typically obtained from carbonate associated sulfate (CAS), where the assumption is that seawater sulfate passively incorporates into carbonate minerals as they precipitate. Through our research, we have found that there are more controls on CAS than was previously assumed, and that oxidized sulfide minerals can result in a false CAS signature. Synchrotron XRF is essential for identifying the sources of sulfur signatures in ancient marine sediments.
Macroalgae Deconstruction
Sulfur plays a crucial role in the growth and metabolism of macroalgae, which are increasingly recognized as a potential source of biofuels. By optimizing sulfur levels, macroalgae can grow more efficiently and produce higher yields of biomass. This enhanced biomass production is critical for biofuel applications, as it directly influences the quantity of algal material available for conversion into sustainable energy sources.
However, macroalgae contain high concentrations of sulfated sugars, which must be broken for deconstruction. These complex carbohydrates, which include sulfated polysaccharides, contribute to the rigidity and stability of algal cell walls. During the process of deconstruction for biofuel production, the breakdown of these sulfated sugars is crucial. Enzymes that target sulfated sugars help to dismantle the algal matrix. Understanding and optimizing the breakdown of sulfated sugars can enhance the efficiency of macroalgae deconstruction processes, improving the overall yield and effectiveness of biofuel production or other applications.
We are currently seeking collaborators to pursue this research.
Sulfur plays a crucial role in the growth and metabolism of macroalgae, which are increasingly recognized as a potential source of biofuels. By optimizing sulfur levels, macroalgae can grow more efficiently and produce higher yields of biomass. This enhanced biomass production is critical for biofuel applications, as it directly influences the quantity of algal material available for conversion into sustainable energy sources.
However, macroalgae contain high concentrations of sulfated sugars, which must be broken for deconstruction. These complex carbohydrates, which include sulfated polysaccharides, contribute to the rigidity and stability of algal cell walls. During the process of deconstruction for biofuel production, the breakdown of these sulfated sugars is crucial. Enzymes that target sulfated sugars help to dismantle the algal matrix. Understanding and optimizing the breakdown of sulfated sugars can enhance the efficiency of macroalgae deconstruction processes, improving the overall yield and effectiveness of biofuel production or other applications.
We are currently seeking collaborators to pursue this research.
