|Education:||B.S. in Biology
University of Nebraska at Lincoln, 1975
|M.S. in Biology
University of Nebraska at Lincoln, 1978
|Ph.D. in Microbiology
University of Nebraska Medical Center, 1992
Areas of interest:
Courses taught: Inquiry lab (Bio 110, SEA Phages), Genetics, Microbiology, Immunology, Infectious Diseases, Environmental Microbiology, Wetlands Biology, Culture of Food and Drink (Interterm), Nebraska’s Water Resources (interterm), Senior Research 495, 496.
I am currently a co-Principle Investigator on the Disability and Rehabilitation Research Project grant held with in the Natural Sciences and Mathematics Division at Doane. The grants primary research focus is on various aspects of biofilm growth and development. Bioflims are clusters of bacteria (and other organisms in nature) that grow attatched to a surface. In the envrionment bioflims are useful entities, providing protection and a collaborative envrionment for microbial communities. However, in the human-impacted envrionment, bioflims are frequently problematic if not highly dangerous. Bioflims in disease situations, such as in lung disease or on prosthetic devices, prove to be extremely resistant to control methodologies, such as antibiotics. New approaches to control bioflims will invovle better understanding of cells attachment to surfaces, production of extracellular polymeric substances (EPS), and cell to cell communitcation (quorum sensing).
Quorum sensing is the mechanism by which many bacteria "talk" to each other, in the envrionment as well as in the laboratory culture. Pseudomonas aeruginosa is common soil organism that forms bioflims both in the natural envrionment and the lungs of cystic fibrosis patients. Like many other quorum sensing microbes, when a threshold concetration is reached the cells begin to behave differently, and "turn on" new sets of genes. Many ot these genes produce substanes that are toxic to surrounding cells, and in human tissue can cause cell damge. The ability to interfere with this communication would have profound effects, and thus we explore way of preventing this signaling mechanism from occuring.
Another area of interest I hold is in wetland microbiology and geomicrobiolgy, particularly that of saline wetlands. Two types of saline wetland are found in Nebraska. The easten saline wetlands and salt flats that featured prominently in the pioneers' overland migration in the 1850's and the western (Sand Hills) saline alkaline wetlands, which provide a much more extreme envrionment for microbial life. The wetlands have been coined "biogeochemical reactors" and are highly likely to contain new and novel organisms that could have new and interesting genes. We visit both of these sites in the Wetland Biology course.
Recent Professional Development:
Year-long sabbatical at Max Planck Institute for Terrestrial Microbiology,Marburg, Germany, 2005-2006.
Project: Two-component signaltransduction in Myxococcus xanthus.
Sabbatical leave at Helmholz Institute for Infectious Disease Research,Hannover, Germany, September – December, 2014. Project: 4D confocal microscopyof Pseudomonas aeruginosa biofilms.
Student Research :
Most students in my lab work in microbiology-related projects, although a wide range of projects have been
-Investigation of biofilm formation by Pseudomonas aeruginosa on a human epithelial cell line, and potential inhibition of biofilm formation by peppermint extract and rosmarinic acid.
-Investigation of effects of a wild bacteriophage on biofilm formation by Pseudomonas aeruginosa. (continuation of project started by student last year)
-Investigation of protease production by Pseudomona aeruginosa growing on contact lenses.
-Microarray analysis of quorum sensing gene expression in P. aeruginosa during stress.
-Development of an antibody to the acyl-homoserine lactone molecule that is the signaling molecule of P. aeruginosa comparison of the microbial diversity of a pristine vs. an altered rainwater basin wetland southeastern Nebraska presence of MRSA (methicillin-resistant Staphylococcus aureus) in long term nursing facilities
R.M. Joeckel, B.J. Ang Clement. Soils, surficial geology, and geomicrobiology of saline-sodic wetlands, North Platte River Valley, Nebraska, USA. Catena 61 (2005) 63-101.
Sulfate-mineral crusts from pyrite weathering and acid rock drainage in the Dakota Formation and Graneros Shale, Jefferson County, Nebraska. R.M. Joeckel, B.J. Ang Clement, L.R. VanFleet Bates. Chemical Geology 215 (2005) 433-452.
Fang, J., Chan, O., Joeckel, R.M., Huang, Y., Wang, Y., Bazylinski, D.A., Moorman, T.B., and Ang Clement, B.J., 2006, Biomarker analysis of microbial diversity in sediments of a saline groundwater seep of Salt Basin, Nebraska. Organic Geochemistry 37: 912-931.
Joeckel, R.M., Burbach, M.E., Wally, K.D., Ang Clement, B.J., Hanson, P.R., and Myers, W.F. (2006). Relationship between bedrock weathering and groundwater in Eastern Nebraska: a preliminary survey. In M.E. Burbach, R.M. Joeckel, & C.A. Flowerday (Eds.). 51st Midwest Ground Water Conference, Program with Abstracts (p. 25). Lincoln: University of Nebraska-Lincoln, School of Natural Resources.
Secondary minerals from extrapedogenic per latus acidic weathering environments at geomorphic edges, Eastern Nebraska, USA. R.M. Joeckel, K.D. Wally, B.J. Ang Clement, P.R. Hanson, J.S. Dillon, S.K. Wilson. Catena 85 (2011) 253–266