Our Research

Halophile Diversity, Ecology and Genomics

Extreme hypersaline viruses can be found infecting bacterial and archaeal hosts in aquatic habitats around the world. We are isolating and characterizing hypersaline archaeal and bacterial hosts and their associated viruses from such sites as the Exportadora de Sal (ESSA) salterns in Guerrero Negro, Baja California, Mexico, as well as hypersaline and alkaline Searles Lake in Mojave Desert, California, USA.

Aquatic Coliforms and Antibiotic Resistance

Fecal coliforms are a major potential public health hazard, especially after rainfall, at urbanized coastal beaches and wetlands. We have used standard counting approaches to enumerate fecal coliforms and antibiotic susceptibility and MIC analyses on fecal coliform isolates to measure environmental risks. More recently we are broadening our investigations to include identifying other antibiotic resistant bacterial isolates.

Heart Urchin Microbiomes

We are currently collaborating with Dr. Bruno Pernet at CSULB and Dr. Alexander Ziegler at the University of Bonn to investigate the microbes associated with sediment burrowing heart urchins, Brisaster townsendii, off the coast of southern California.

Salt Marsh Sea Level Rise Impacts and Restoration

Sea level rise is a major threat to already heavily impacted urban marshes in southern California.  We have collaborated with Dr. Christine Whitcraft at CSULB to investigate the impact of increased inundation on salt marsh sediment communities associated with the Spartina cordgrass zone in the restored Huntington Beach Wetland salt marsh.  We have used both marsh organs and boxes to manipulate sea level and studied impacts on plants, invertebrates, fungi and bacteria. More recently we are investigating the impact of sediment amendment and plant restoration on microbes of the Seal Beach National Wildlife Refuge.

Near-shore Hydrothermal Vent Communities

We have studied the chemosynthetic microbial mats found in intertidal and subtidal hydrothermal vents found near White Point in San Pedro, CA as shallow analogs of their deep-sea counterparts. We have collaborated with the lab of Dr. Victoria Orphan at Cal. Tech. University to use a combination of molecular sequencing, FISH microscopy and radiotracer studies to investigate sulfur cycling in these biofilms.

Phototrophic Microbialites

During his doctorate and post-doctoral research, Dr. Dillon studied photosynthetic microbial mats in both geothermal hot springs in Yellowstone National Park and hypersaline salterns in Baja CA, Mexico. More recently a master’s student in his lab has investigated manganese-oxidizing microbialites in the Badwater Basin area of Death Valley National Park using cultivation and molecular sequencing approaches.

Funding

Recent projects have been funded by:

Additional, there has been student support by: