The Cápiro Lab

Environmental Microbiology, Bioremediation, & Groundwater Contaminant Fate and Transport

The Cápiro lab studies the transformation of emerging and traditional organic contaminants in the environment that cause harmful effects on the environment and human health. We are particularly interested in revealing the degradation pathways, microbial dynamics and their interactions with biotic and abiotic factors.

FUNDAMENTAL RESEARCH QUESTIONS

Contaminant TRANSFORMATION PROCESS

Some organic pollutants can remain in the environment for a long time (decades to centuries) even when present at very low concentration, e.g., persistent organic pollutants (POPs). POPs can transport long distances from their original sources, and biomagnify in the food chain. Moreover, their transformations are complex, affected by environmental matrices, resulting in different transformation byproducts, pathways and rates. The complexity these processes make POPs challenging on the regional, national and global scales.

In the Cápiro Lab, we conduct batch reactor experiments, extend to columns experiments and scale up to aquifer cell studies. Each set-up is highly reductionist, focusing on specific objects and conditions, e.g., specific pollutant compounds, environmental compartments, and redox conditions. In the rationally designed series of experiments, we monitor the geochemical parameters, identify and quantify the parent compounds and transformation products that give insights into transformation pathways and rates. The results are also helpful for modelers to develop mathematical modeling and decision tool for biotransformation and bioremediation process.

APPLICATIONS OF MOLECULAR-BASED AND OMICS-APPROACHES

What is the role of the microbial community in contaminated environments? The functions of microorganisms are ultimately determined by their molecular components, i.e., DNA sequences and expressed enzymes/proteins. A number of molecular methods, e.g., next-generation sequencing, genomics, transcriptomics, proteomics, and metabolomics, have been developed to explore the microbial world, and particularly enhance our understanding of the mechanisms involved. In practice, intricate conditions and factors impact the microbial activities.

In the Cápiro Lab, we develop microcosms that allow researchers to rationally establish natural microbial ecosystems and efficiently simulate the contamination events in the experimental systems. We collect biomass from the microcosms and employ DNA/RNA extraction from the samples. Genomic DNA and 16S rRNA sequencing results give us information regarding complex microbial structure and diversity. Extraction of mRNA and qPCR results furnish information about the gene expression under varied conditions. By applying molecular-based approaches, we have a comprehensive understanding of contaminants degradation mechanisms, and the factors that impact the functions and dynamics of the indigenous microbial communities. It could provide a perspective on the microbial consortia needed for the bioremediation process. And our findings of gene expression could be used by microbial genetics community to engineer the specific degraders in their own studies.

Sample collection at Robins AFB