B.S. 1975, Whitworth College, Spokane, WA
Ph.D. 1982, University of Wisconsin-Milwaukee
Postdoctoral Fellow, University of Washington, Seattle, WA
Research Associate, Harvard University, Cambridge, MA
Microbial Ecology
The research in my laboratory involves the study of microorganisms and their interactions with their biotic and abiotic environments. These studies generally use a combination of molecular techniques and traditional culture/enrichment microbiology to examine microbial and/or gene diversity, abundance and activity.
Currently, we are focused on examining microbial communities in anaerobic digesters in collaboration with colleagues in the Department of Civil, Construction and Environmental Engineering, and Department of Mathematics, Statistics and Computer Science at Marquette. The goals of this research are to enhance methane production and to determine the identity of beneficial microorganisms that can be used in bioaugmention to significantly shorten new digester startup times and/or to aid the recovery of stressed digesters. Anaerobic digestion is a microbial community interrelated process that breaks down organic matter ultimately resulting in the production of biogas, containing methane. Methane is produced by archaea known as methanogens and we are using a variety of molecular techniques to determine their abundance, activity and diversity in different anaerobic biomass. However, they are not the only microorganisms involved in the organic breakdown, so we have been developing molecular methods to analyze the members of the microbial community participating in the steps preceding methane production. The information we are obtaining will be used to design anaerobic cultures that can bioaugment a variety of different digester situations.
An additional project involves the role of microbial biofilms in biofouling by larval and adult zebra (Dreissena polymorpha) and quagga (D. bugensis) mussels. The zebra and quagga mussels are bivalves that invaded the North American Great Lakes sometime in the mid-to-late 1980s and have since spread through interconnected waterways across much of the mid-western and eastern United States. Both of these animals represent potentially expensive fouling problems to industrial and municipal concerns. Our field studies have shown that the effect of natural biofilms on zebra mussel larval attachment varies between the substrata that the biofilms develop on. On one substratum biofilms stimulated larval attachment while on another they had no effect. Laboratory studies showed that natural biofilms could also influence the byssal thread reattachment of young adult mussels. Additional experiments demonstrated that monospecies bacterial biofilms on specific substrata and in some cases the cell-free extracellular polymers of these biofilms inhibited reattachment of young adult mussels. Currently, the research is focused on the study of the extracellular polymers of these bacteria. The goal is to determine if natural products can be isolated from the bacteria that either stimulate or more importantly inhibit attachment of zebra and/or quagga mussels.
Periodically, we study biofilm formation by oral microorganisms and its control in collaboration with investigators from the Marquette University School of Dentistry. The goal is to find better methods to prevent infection and re-infection of teeth and tissues.
Selected Publications
Tale, V.P., Maki, J.S., Struble, C.R., and Zitomer, D.H. 2011. Methanogen community structure-activity relationship and bioaugmentation of overloaded anaerobic digesters. Water Research 45: 5249-5256.
Konkol, N.R., Bruckner, J.R., Aguilar, C., Lovalvo, D. and Maki, J.S. 2010. Dominance of epiphytic filaments Thiothrix spp. on an aquatic macrophyte in a hydrothermal vent flume in Sedge Bay, Yellowstone Lake, Wyoming. Microbial Ecology 60: 528-538.
Choong, A.M.F., Maki, J.S., Ikhwan, J.T.B., Chen, C.L., Ritschof, D., and Teo, S.S.M. 2010. Pharmaceuticals as antifoulants: inhibition of growth and effect on adhesion of marine bacteria. Pp.221-246, In, Biofouling: Types, Impact and Antifouling, J. Chan and S. Wong, eds., Nova Science Publishers, Inc. Hauppage, NY.
Schauer-Gimenez, A.E., Zitomer, D.H., Maki, J.S., and Struble, C. 2010. Bioaugmentation for improved recovery of anaerobic digesters after toxicant exposure. Water Research 44: 3555-3564.
Baer, J., and Maki, J.S. 2010. In Vitro evaluation of the antimicrobial effect of three endodontic sealers mixed with amoxicillin. Journal of Endodontics 36:1170-1173.
Schauer-Gimenez, A.E., Maki J.S., Struble, C.A., and Zitomer, D.H. 2009 Bioaugmentation with hydrogen-utilizers for anaerobic digestion recovery. In, Proceedings of the Water Environment Federation Technical Exposition and Conference (WEFTEC 2009), 632-640.
Townsend, C., and Maki, J.S. 2009. An in vitro comparison of new irrigation and agitation techniques to ultrasonic agitation in removing bacteria from a simulated root canal. Journal of Endodontics 35: 1040-1043.
Meeting Presentations
Morris, R.L., A. Schauer-Gimenez, U. Bhattad, J. Boyle, C. Struble, D.H. Zitomer, and J.S. Maki (2010) Comparison of methyl coenzyme M reductase gene and mRNA diversity in anaerobic digesters. Q-860 in Abstracts of 110th General Meeting, American Society for Microbiology, San Diego, CA, May 23-27.
Schauer-Gimenez, A., R.L. Morris, J.S. Maki, C.A. Struble, and D.H. Zitomer (2010) Bioaugmentation aids in the recovery of lab-scale anaerobic digesters exposed to a toxicant. Q876 in Abstracts of 110th General Meeting, American Society for Microbiology, San Diego, CA, May 23-27.
Bhattad, U.H., A. Schauer-Gimenez, D. Zitomer, J.S. Maki, and C. Struble (2010) Feasibility of freeze-drying beneficial anaerobic methanogenic cultures in air. Q-883 in Abstracts of 110th General Meeting, American Society for Microbiology, San Diego, CA, May 23-27.
Tale, V.P., D. Zitomer, J.S. Maki, C. Struble (2010) Bioaugmenting with propionate-acclimated culture helps restore the archael community of an anaerobic digester following an organic overload. OS-989 in Abstracts of 110th General Meeting, American Society for Microbiology, San Diego, CA, May 23-27.
Morris, R.L., A. Schauer-Gimenez, U. Bhattad, D.H. Zitomer, and J.S. Maki (2010) Monitoring methanogen communities in anaerobic digesters using quantitative polymerase chain reaction amplification of mcrA. PS.20.024, ISME 13, 13th International Symposium on Microbial Ecology, Seattle, WA, August 22-27.
Bhattad, U.H., J.S. Maki, C.A. Struble, A.E. Schauer-Gimenez, and D.H. Zitomer (2010) Culture conditions and cryoprotectant addition influences preservation of methanogenic activity after freeze-drying in air. 12th International Water Association Specialist Conference on Anaerobic Digestion, Guadalajara, Mexico, Oct 31-4 Nov, 2010.
Tale, V.P., J.S. Maki, C.R. Struble and D.H. Zitomer (2010) Bioaugmentation can improve anaerobic digester performance after organic overload. 12th International Water Association Specialist Conference on Anaerobic Digestion, Guadalajara, Mexico, Oct 31-4 Nov, 2010.
Current Students
Prince Mathai (Ph.D. student)
Dr. Maki is currently accepting new Ph.D. students into his lab
Biological Sciences Department
Marquette University, Wehr Life Sciences
(Directions/campus map)
P.O. Box 1881
Milwaukee, WI 53201-1881
(414) 288-7355
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