The organic fraction of airborne particulate matter is heterogenous in chemistry and origin. We estimate that up to 25% of this fraction originates from biological sources. In order to assess the biological contribution, we measure biopolymers (carbohydrates, phospholipids, proteins, and DNA), and construct 16S clone libraries to understand the source of biological matter. As biological particles have a pronounced health effect, we also assess the genotoxicity of particulate matter to bacterial and eukaryal cells.
Airborne particulate matter will be analyzed for its total biological load—carbohydrate6, protein5,
phospholipid and DNA content—as well as its total carbon content (both inorganic and organic).
Particulate matter will be eluted from filters into sterile, pyrogen-free water. Carbohydrates are measured
using a sensitive colorimetric assay of phenol conjugation to monomeric sugars following sulfuric acid
digestion using glucose as a standard. Protein associations with atmospheric aerosols are determined
using selected quantitation of Nano-Orange dye from a sensitive fluorescence assay, which uses bovine
serum albumin as a standard (Invitrogen). Phospholipid associations with atmospheric aerosols are
determined using a simple colorimetric assay of airborne particulate matter extracted into chloroformmethanol
mixtures. The lipids present in the solvent extracts are quantitatively subject to a persulfate
digestion, which is calibrated against a ß-glycerol phosphate standard.
The gulf project compares particulate matter collected from Grand Isle, LA and Sea Rim, TX in order to investigate how the biological fraction has been affected by the Deepwater Horizon oil spill. The University of Colorado published an article describing our work.
The Manitou project characterizes the biological fraction of particulate matter from a semi-pristine high-alpine outdoor environment, with the goal of understanding the baseline for outdoor bioaerosols.
In summer 2012, we collected aerosol samples downwind of a forest fire on the Colorado Front Range. These samples will be analyzed for bioaerosol load and toxicity.
Personnel: Alina Handorean, Jane Turner, Bharath Prithiviraj, Odessa Gomez
Past Personnel: Mari Rodriguez
Personnel: Kevin McCabe, Jane Turner, Diedra Gustafson
In one phase of this study, we collected corroded concrete biofilm samples from ten cities acrosso the United States. We will use V4V5 16S amplicon sequencing on the Illumina MiSeq platform and will collect environmental data such as pH, moisture content, headspace gasses, and sulfur content to assess how the corrosion community differs across environmental gradients.
In the second phase of this work, a metal-based antimicrobial coating will be designed and tested in lab and in field manholes. We exposed treated and untreated concrete coupons in a working sanitary manhole for time periods of 1 month to 12 months. These samples were analyzed for microbial community composition, surface chemistry, and extent of corrosion. Additionally, we will perform laboratory inhibition studies of the product using sulfide-oxidizing bacterial cultures.
Personnel: Alison Ling, Anna Campbell
Personnel: Kevin McCabe, Jane Turner,
Past Personnel: Jordan Peccia, Sarahann Dow, Lars Angenent
Our work on electromagnetic fields (EMF) arose from our studies of electrically enhanced filter systems and their ability, not only to capture bioaerosols, but also inactivate microbes on the filter surface. This intensively collaborative endeavor, in conjunction with Frank Barnes in Electrical Engineering at CU Boulder, seeks to identify the molecular mechanism/s by which EMF exert effects on biological systems. We have demonstrated changes in growth kinetics of cancer cell lines and, more recently, bacteria in response to shielding or reducing the Earth's magnetic field. These micro-Tesla level changes are on the order of what one might observe between indoor versus outdoor settings, or perhaps more importantly to the biological sciences community, between cell culture incubators. While large epidemiological studies of the effects of EMF on human health have been carried out for decades, these efforts are hampered by a lack of understanding of the most fundamental effects of EMF at the subatomic to molecular level.
Past Personnel: EJ Sheehan, Kevin McCabe
Benzotriazoles are a anti-corrosion agent used in aircraft deicing fluid and other industrial applications. These compounds are resistant to environmental degradation and inhibitory to bacterial growth.
Benzotriazoles can form strong complexes with transition metals and enable the removal of toxic metals from industrial waste streams.
Past Personnel: Muna Abu-Dalo, Jeff Cornell, Cyndee Gruden, Ivette O'Brien