April 2011

Document Type


Degree Name



Oregon Health & Science University


Laboratory-generated samples, and samples from a toluene-“contaminated” model aquifer were used to systematically evaluate the efficacy of cryogenic preservation and storage for the molecular characterization of microorganisms in sediment. Using qPCR, RT-qPCR, and PCR-SSCP, no significant differences were observed between frozen and unfrozen sediment. Furthermore, it was demonstrated the cryogenic coring, i.e. freezing the core in-situ prior to extraction to the surface, was a viable way to accurately characterize subsurface microbial populations. Using functional genes as biomarkers, significant differences were observed between sediment-attached and suspended toluene-degrading microbial communities from paired high-resolution sediment and water samples from a model aquifer. Results from sediment were in better agreement with groundwater chemistry suggesting that functional genes detected in groundwater may not be highly expressed, and may have been artifacts of transport. This was la




Institute of Environmental Health


School of Medicine



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.