Research Topics

Research Summary Figure 2014


Research Overview

The objective of our research activities is to obtain a mechanistic understanding of the “why” and “how” of the environmental behavior of biologically-active organic molecules with implications for environmental contamination, soil fertility, agricultural productivity, and ecosystem health. We are particularly interested in the fate and effects of organic contaminants including herbicides, antibiotics and natural toxins and in the reactivity and fate of important organic substrates and macromolecules in environmental matrices. Our investigative approaches employ a combination of experimental and computational techniques to resolve the mechanisms of the chemical and biochemical interactions relevant to the environmental chemistry and toxicology of these molecules. The long-term goal of our research is to achieve a mechanism-based quantitative evaluation of the potential implications of these bioactive molecules for environmental fate and exposure, chemical transformation, biotechnology, ecosystem health, and carbon dynamics in aquatic and terrestrial environments.


Research Techniques

Molecular Environmental Chemistry: X-ray diffraction; Solid-state and liquid-state NMR; Fluorescence quenching spectroscopy; Infrared spectroscopy; Scanning electron microscopy; Molecular dynamics simulations.

Molecular Environmental Biochemistry: Liquid-chromatography-mass spectrometry, Stable isotope-assisted metabolomics; liquid-state NMR; Numerical flux modeling of metabolic network; Molecular docking simulations; Flow Cytometry.


Current Research Activities

Microbial Carbon Metabolism (Lignin and Cellulose)
Personnel:
Nanqing Zhou (Postdoctoral researcher). Project: Metabolic network for lignin catabolism in bacterial vesicles
Pandeeswari Jeeva (Postdoctoral researcher). Project: Metabolism of sugar and aromatic substrate mixtures
Kelly Teifel (Undergraduate student). Project: Bacterial metabolism of plastics polymers and monomers
Joey Brogan (Undergraduate student). Project: Microscopic imaging of bacterial membrane vesicles

Microbial Carbon Metabolism (PLastics)
Personnel:
Nanqing Zhou (Postdoctoral researcher). Project: Bacterial metabolism of plastics polymers
Norah Chen (Graduate student). Project: Bacterial metabolism of plastic monomers
Kelly Teifel (Undergraduate student). Project: Metabolism of bacterial membrane vesicles
Lynna Deng (Undergraduate student). Project: Bacterial metabolism of plastic monomers

Molecular Chemistry of Natural Organic Matter and Macromolecules
Personnel:
Jiaxing Wang (Graduate researcher). Project: Interfacial interactions of organic mixtures at clay interfaces
Aurore Niyitanga Manzi (Graduate student). Project: Nutrient recycling by extracellular enzymes
Rebecca Wilson (Graduate student). Project: Interfacial interactions of biomolecules at clay interfaces

Catalysis and Transformation of Biomolecules at Mineral Interfaces
Personnel:
Benjamin Barrios Ceda (Postdoctoral researcher). Project: Biomolecule transformation at mineral interfaces
Jade Basinski (Graduate researcher). Project: Mineral catalysis and phosphorus recycling
Aurore Niyitanga Manzi (Graduate researcher). Project: Mineral catalysis and phosphorus recycling
Marcos Sanchez (Undergraduate researcher). Project: Biomolecule transformation at mineral interfaces

Chemistry of Natural Biopolymers and Synthetic Polymers
Personnel:
Nasrin Naderi Beni (Postdoctoral researcher). Project: Interfacial chemistry of plastics
Haklae Lee (Graduate researcher). Project: Interfacial chemistry of plastics
Eva durance (Research Technician). Project: Characterizaton of bacterial polymers
Rohan (High-school intern). Project: Molecular simulations of three-dimensional structures of bacterial polymeric substances



Instruments

Liquid Chromatography/Mass Spectrometery (LC/MS), Thermo Scientific Q Exactive
The Q Exactive LC/MS is used for precise measurements of targeted and non-targeted analytes using reverse-phase liquid chromatography mass spectrometry. This instrument is applied to determine the identity and abundance of intra and extracellular metabolites in order to monitor bacterial metabolism and contaminant degradation.
Powder X-ray Diffractometer (XRD), Bruker D8 Advance
The XRD is used to monitor interactions of organic substrates and contaminants with expandable clay minerals. Our XRD instrument is equipped with temperature-humidity stage to allow control of both temperature and moisture levels during the run.
Fluorescence Spectrophotometer, Agilent Technologies Cary Eclipse
The fluorescence spectrophotometer is used to monitor levels and/or changes in fluorescing organic molecules.
Incubator Shaker, New Brunswick Scientific
Our lab is equipped with several incubator shakers to maintain different growth conditions for our bacterial work.

The Lab