Dr. Gerlach’s research focuses on the development of biofilm and extremophile technologies for beneficial purposes.  Biofilms are structurally and metabolically complex communities of microorganisms enmeshed in extracellular polymeric substances (EPS) that commonly consist of complex polysaccharides.  Biofilms and extremophilic microbes are often more tolerant to environmental stresses and provide unique opportunities in biotechnology.

Current Research

1. the use of biofilms in carbon dioxide sequestration – Biofilms can be used to reduce the permeability of porous media in the deep subsurface.  Such engineered subsurface biofilm barriers have been used for the control or containment of environmental contaminants (Figure 1).  We are currently investigating the utility of biofilms grown at the high pressures encountered in deep subsurface formations, such as brine aquifers or depleted oil reservoirs, which are the target for CO₂ injection.  Our recent work has shown that biofilms can reduce the permeability of rock cores at high pressures and resist the exposure to supercritical CO₂, which forms at the pressure (> 71 bar) and moderate temperatures (> 32 °C) encountered in these formations, which are often 800 m deep or deeper (Figure 2).  (Funding: Department of Energy, ZERT, http://www.montana.edu/zert/home.php, Funding: DOE, publication Mitchell et al. 2008 - The International Journal on Greenhouse Gas Control, see below for full citation)
   
   
2. the influence of cellulose degrading and fermenting organisms on the transport of heavy metals and radionuclides.  The degradation of cellulosic and other organic materials, often co-disposed with heavy metal and radioactive wastes can influence the speciation and mobility of metals and radionuclides.  This project investigates the potential effect that the utilization of organics present in the subsurface has on the mobility of heavy metals and radionuclides.  (Funding Department of Energy, Environmental Remediation Science Program, publications (several)– see
   
   
3. the transformation of mixtures of environmental contaminants, specifically mixtures of explosives with other commonly observed environmental contaminants such as metals and chlorinated solvents.  (various DoD and DOE related funding sources, publications (several)– see
   
   
4. the influence of supercritical fluids on the survival of microorganisms.  Supercritical CO₂ (scCO₂) has been shown to have a biocidal effect on microorganisms.  We have recently shown that biofilms are significantly more resistant to scCO₂ exposure.  (Funding: DOE, publication Mitchell et al. 2008 - The Journal of Supercritical Fluids, see below for full citation)

Other (currently small) projects are investigating the use of biofilm and extremophilic microbes for bioenergy applications.

Figure 1: Schematic of a subsurface biofilm barrier for the control of contaminated groundwater.



Figure 2: Schematic of a deep subsurface biofilm barrier to enhance the sequestration of carbon dioxide.

We are currently trying to recruit graduate students
with interest in the following areas

1. Influence of mineral-precipitating biofilms on reactive transport in porous media
2. Use of biofilms in the sequestration of carbon dioxide
3. Influence of supercritical fluids on the survival of microorganisms

A link to the full announcement can be found at http://www.biofilm.montana.edu/~robin_g/

Selected Publications:

Mitchell, A.C.; Phillips, A.J.; Hamilton, M.A.; Gerlach, R.; Hollis, K.; Kaszuba, J.P.; Cunningham, A.B. (2008): Resilience of planktonic and biofilm cultures to supercritical CO2. The Journal of Supercritical Fluids. 47(2):318-325. doi:10.1016/j.supflu.2008.07.005

Mitchell, A.C.; Phillips, A.J.; Hiebert, R.; Gerlach, R.; Spangler, L.; Cunningham, A.B. (2008): Biofilm enhanced geologic sequestration of supercritical CO2. The International Journal on Greenhouse Gas Control. doi:10.1016/j.ijggc.2008.05.002

Ziganshin, A.M.; Gerlach, R; Borch, T; Naumov, A.V.; Naumova, R.P. (2007): Production of Eight Different Hydride Complexes and Nitrite Release from 2,4,6-Trinitrotoluene by Yarrowia lipolytica. Appl. Environ. Microbiol. 73(24):7898-7905

Cunningham, A.B.; Sharp, R.S.; Caccavo Jr, F.; Gerlach, R. (2007): Effects of Starvation on Bacterial Transport Through Porous Media. Advances in Water Resources. 30(6-7):1583-1592.

Sharp; R.R.; Stoodley, P.; Adgie, M.; Gerlach, R.; Cunningham, A.B. (2005): Visualization and characterization of dynamic patterns of flow, growth, and activity of biofilms growing in porous media. Water Science and Technology. 52, 7:85-90.

Borch, T.; Inskeep W.P.; Harwood, J.A.; R. Gerlach, R. (2005): Impact of Ferrihydrite and Anthraquinone-2,6-Disulphonate on the Reductive Transformation of 2,4,6-Trinitrotoluene by a Gram Positive Fermenting Bacterium. Environmental Science and Technology. 39, 18:7126-7133.

Seymour, J.D.; Gage, J.P.; Codd, S.L.; Gerlach, R. (2004): Anomalous Fluid Transport in Porous Media Induced by Biofilm Growth. Physical Review Letters. 93, 19:8101-8104.

Borch, T.; Gerlach, R. (2004): Use of Reversed Phase High-Performance Liquid Chromatography-Diode Array Detection for Complete Separation of 2,4,6-Trinitrotoluene Metabolites and EPA Method 8330 Explosives: Influence of Column Temperature and Ion-Pair Reagent. Journal of Chromatography A. 1022: 83-94.

Bouwer, E.J., Rijnaarts, H.H.M., Cunningham, A.B. & Gerlach, R. (2000): Biofilms in Porous Media. In Bryers, J.D. (Ed.): Biofilms II: Process Analysis and Applications. Wiley-Liss, Inc. pp. 123-158.

Gerlach, R., Cunningham, A.B. & Caccavo, F. Jr. (2000): Dissimilatory Iron-Reducing Bacteria Influence the Performance of Zero-Valent Iron. Environmental Science and Technology, 34, 2461-2464.

A full list of publications and presentations can be found at publications (several)– see

Current Laboratory Personnel:

Erin Field,
Ph.D. Student, Microbiology
efield@biofilm.montana.edu

Laura Jennings,
Visiting Ph.D. Student from Cornell University, Environmental Engineering
ljennings@biofilm.montana.edu

Andy Pannier,
Masters Student, Microbiology
andy.pannier@biofilm.montana.edu

Stacy Parks,
Masters Student, Chemical and Biological Engineering
stacy.biebel@biofilm.montana.edu

Logan Schultz,
Masters Student, Chemical and Biological Engineering
lschultz@biofilm.montana.edu

Laura Wheeler,
Masters Student, Chemical and Biological Engineering
laura.wheeler@biofilm.montana.edu

Robert Fortenberry,
Undergraduate Researcher, Chemical and Biological Engineering
robert.fortenberry@biofilm.montana.edu

Collaborators:

Apel W.A. - Idaho National Laboratory
Apple, M. – University of Montana
Borch T. - Colorado State University
Dohnalkova, A. - Pacific Northwest National Laboratory
Hiebert, R. – MSE Technologies Applications
Holben, W. – University of Montana
Hollis, K. - Los Alamos National Laboratory
Kaszuba, J. - Los Alamos National Laboratory
Lee B. - Idaho National Laboratory
Miller, S. – University of Montana
Naumova, R. - Kaszan State University
North-Abbot, M. – University of Montana
Sharp R.R. - Manhattan College
Viamajala S. - Utah State University
Zhou, X. – University of Montana
Ziganshin, A. - Kaszan State University

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