Chlorobiaceae and Acidobacteria physiology
The best characterized Chlorobiaceae (green sulfur bacteria) are anaerobic anoxygenic phototrophs that oxidize inorganic sulfur compounds (sulfide, elemental sulfur, and thiosulfate) to provide electrons that are used to fix carbon dioxide for growth. Many of these bacteria can also assimilate simple organic compounds like acetate and pyruvate. Through a DOE Community Science Program grant, we are gathering metabolomic data from model Chlorobiaceae to validate and gap-fill predicted metabolic models. Ultimately, we hope to engineer Chlorobiaceae to synthesize desired products from carbon dioxide while consuming hydrogen sulfide. This project continues the lab's long term interest in these fascinating bacteria. The DOE project will also collect metabolomic data from multiple Acidobacteria, which are abundant in soils and are likely important for soil organic matter decomposition. However, little is known about their metabolism.
Delaware Microbiome and Community Sequencing Projects
With NSF support through Project WiCCED, we are developing an amplicon sequencing method to simultaneously collect sequence for 16S and 18S rRNA genes along with ten additional functional genes to profile microbial community structure and functional potential for tens of environmental samples in a single Illumina sequencing run. We've established a Microbiome Core for offering this method. This method will be used to map microbial community structure and functional genes across the regional landscape in conjunction with environmental data and through time. This will guide additional sequencing and isolation efforts to better understand microbial populations and recover novel microbes. Undergraduate research projects under this larger program are focused on the Delaware River and local Delaware ponds.
Microbial Epigenetics
Supported by the Keck Foundation, this project is using PacBio sequencing to identify modified DNA bases in diverse bacteria and archaea to understand whether epigenetics is widely employed in the microbial world as a mechanism to regulate gene expression, particularly under energy stress. This project is a collaboration with Dr. Jen Biddle and Dr. Adam Marsh with Dr. Katie Kalis, who earned her M.S. and Ph.D. in the Hanson lab, developing methods for deeply analyzing and visualizing PacBio modification data.
Actinobacterial Genetics
Supported by an EDGE program grant from the NSF led by Prof. Julie Maresca, this project will develop tools to understand how some members of the Microbacteriaceae, a group of Actinobacteria, use light as information rather than as an energy source. Tools under development include targeted gene inactivation, transposon mutagenesis, and plasmid systems.
