My Research Interests
My research interests are where microbiology and environmental engineering meet. In particular, my lab investigates the ability for microbes to degrade pollutants in both engineered and natural environments, the interaction of metals, microbes, and disinfection byproducts, the effects of pollutants on microbial communities, and the diversity and abundance of bacteria and genes that degrade pollutants. I typically use DNA and RNA based methodologies and bioinformatics in my studies. Here are my current projects, the students working on them, and publications related to the current work.
Current Projects
Remediation of chlorinated pollutants with simultaneous amendment with natural organochlorines
Graduate Student: Xuewen Wang, Undergraduate Student: Matthew Brooks
This
project is investigating the enhanced degradation of chlorinated ethenes by anaerobic dechlorinating bacteria while under the co-presence of
naturally occurring organochlorine compounds. The objective is to determine
whether natural organochlorines can ‘prime’ this bacterial degradation process chlorinated ethenes degrade faster and more completely. This research may
translate into the development of specialized bioreactors, cultures, or amendments for the treatment of
sites contaminated with difficult-to-degrade chlorinated compounds.
Publications related to Organohalide Respiration
Krzmarzick, M. J., H. Miller, T. Yan, and P. J. Novak. (2014). Novel Firmicutes
group implicated in the
dechlorination of two chlorinated xanthones, analogues for natural
organochlorines. Applied and Environmental Microbiology, 80:1210-1218.
Krzmarzick, M. J., P. J. McNamara, B. B. Crary, and *P. J. Novak.
(2013) Abundance and diversity of organohalide-respiring bacteria in lake
sediments across a geographical sulfur gradient. FEMS Microbiology Ecology 84:248-258.
Krzmarzick, M. J., B. B. Crary, J. J. Harding, O. O. Oyerinde, A.
C. Leri, S. C. B. Myneni, and P. J. Novak. (2012) Natural niche
for organohalide-respiring Chloroflexi. Applied
and Environmental Microbiology 78:393-401.
Anaerobic degradation of triclosan
Ada Xiong (visiting scholar)
In Collaboration with Dr. Patrick McNamara's Lab at Marquette
University http://www.eng.mu.edu/mcnamara/index.html
This project is investigating the anaerobic microbial transformations of the commonly used household product triclosan.
Publications:
McNamara, P. J. and M. J. Krzmarzick. (2013) Triclosan
enriches for Dehalococcoides-like Chloroflexi in anaerobic soil at
environmentally relevant concentrations. FEMS
Microbiology Letters 344:48-52.
Response of Surface Soil Microbial Communities to
Fracing Fluids
Graduate Student: Jeanne Carroll, Undergraduate Student: Aubrey McCutchan
Six
commonly used fracing fluid mixtures were prepared in the laboratory and
amended to surface soil in microcosms. The soil microbial communities degraded the bulk of
the organic carbon of the fluids within 6 weeks, though some mixtures were not
as degraded as others. The degradative response will soon be better
characterized by investigating the RNA and DNA of the soil microbial community
during exposure and degradation. This project has the potential of determining the relative
recalcitrance, or degradability, of different fracing fluid mixtures in
surface soils.
Aubrey is funded by an Oklahoma State University Wentz Scholarship. Additional funding for this work is pending.
Graduate Student: Xiang Fu
Disinfection byproducts are formed in water treatment processes to disinfect against pathogens. Though the disinfection of water is necessary to make it safe to drink, disinfection byproducts are a health concern as well. Understanding how these disinfection byproducts are formed is important to reducing human exposures. Trace elements affect microbial physiology and differ greatly between water treatment systems, and these change in physiology in turn affects disinfection byproduct precursor formation. In this research, Xiang is investigating the effects of trace elements on heavy metals on cellular physiology with regards to the production of disinfection byproduct precursors.
Funding for this work is pending.
The aftermath of Fu's research talk in group meeting, or is this a Pollock?
Disinfection byproducts are formed in water treatment processes to disinfect against pathogens. Though the disinfection of water is necessary to make it safe to drink, disinfection byproducts are a health concern as well. Understanding how these disinfection byproducts are formed is important to reducing human exposures. Trace elements affect microbial physiology and differ greatly between water treatment systems, and these change in physiology in turn affects disinfection byproduct precursor formation. In this research, Xiang is investigating the effects of trace elements on heavy metals on cellular physiology with regards to the production of disinfection byproduct precursors.
Funding for this work is pending.
The aftermath of Fu's research talk in group meeting, or is this a Pollock?
Optimization of Anammox Growth for Mainstream Wastewater Treatment
Graduate Student: Xiang Fu
Nitrogen is a major wastewater pollutant, leading to algae blooms and other environmental issues. Anammox are a group of key bacteria in the removal of nitrogen from the environment, and can be used to remove nitrogen from wastewater with less energy inputs than alternative methods. This project, in collaboration with Jim Field and Reyes Sierra-Alvarez at the University of Arizona, seeks to develop and optimize anammox growth from the sludge digester side-stream for bio-augmentation to the wastewater treatment plant main-stream, thus removing significantly more nitrogen.
Funding: National Science Foundation (Award# 1705088)
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1705088&HistoricalAwards=false
Dry Ice Day !!
