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oai:www.ideals.illinois.edu:2142/49750 2023-07-11 col_2142_5131 col_2142_16338 com_2142_5130 com_2142_16337 com_2142_14793 com_2142_8903

Methanosarcina humic lakes methanogen Whitaker, Rachel J. Whitaker, Rachel J. Metcalf, William W. Olsen, Gary J. Slauch, James M. Youngblut, Nicholas 2014-05-30T17:07:50Z 2014-05-30T17:07:50Z 2016-09-22T20:59:25Z 2014-05 2014-05-30T17:07:50Z 2014-05 Microbial diversity, both genetic and phenotypic, is a product of evolutionary and ecological processes interacting at multiple levels of biological organization. High-throughput sequencing is providing a means to resolve the vast amount of genetic diversity in microbial assemblages. However, a current fundamental challenge is associating genetic diversity, whether at the community or population scale, to phenotypic variation that defines ecological roles and dictates how microbial community diversity and ecosystem functioning respond to environmental change. In this body of work, I have used sequencing-based techniques to identify ecological differentiation at taxonomic scales ranging from a whole bacterial community to a single population of methanogenic archaea. At the broadest taxonomic scale, I used a whole-ecosystem disturbance along with 16S rRNA 454-pyrosequencing to identify ecologically relevant distinctions among taxonomic groups defined at various taxonomic scales. The findings showed that bacterial lineages require different taxonomic definitions to capture ecological patterns. At a more refined taxonomic breadth, I used a culture-independent approach to elucidate how methanogen community diversity was distributed within and between a set of freshwater lakes and also identified the ecological processes dictating this spatial distribution of diversity. Finally, at the highest resolution, I employed a comparative genomics approach to identify genomic signals of adaptive evolution in a Methanosarcina mazei population in order to link genetic variation to the ecological processes that define spatial and temporal distributions of methanogen populations. Together, this work has helped to resolve the interdependencies between genetic diversity and ecological processes, which concomitantly act to create and maintain microbial diversity across time and space. Item withdrawn by Laura Spradlin (lspradl2@illinois.edu) on 2014-01-03T14:30:26Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 2 Youngblut_Nicholas.docx: 16351841 bytes, checksum: a476dc03cd1d4fc0592dee17ed2716e3 (MD5) Youngblut_Nicholas.pdf: 10863054 bytes, checksum: 634658680a2f7783bdcef5e98352d1e6 (MD5) Made available in DSpace on 2014-05-30T17:07:50Z (GMT). No. of bitstreams: 3 Nicholas_Youngblut.pdf: 10862446 bytes, checksum: 87e31ba1ce792ffd4b4dd20c01e13977 (MD5) Nicholas_Youngblut.docx: 16354205 bytes, checksum: 6554f72709fa0c0c1e898d28fff4d68a (MD5) license.txt: 4068 bytes, checksum: b005bd44ee560973c60ae354a776c44b (MD5) Restriction data tranferred 2014-07-01T11:39:30-05:00 Original Data Group with Access UIUC Users [automated] Release Date: 2016-05-30 12:09:03 UTC Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Seth Robbins (robbins.sd@gmail.com) on 2014-05-30T17:09:59Z Item is restricted until 2016-05-30T17:09:03Z U of I Only Restriction Lifted for Item 49801 on 2016-09-22T20:59:25Z. http://hdl.handle.net/2142/49750 en Copyright 2014 Nicholas Youngblut microbial community taxonomic scale population genomics Identifying ecological differentiation in microbial communities across taxonomic scales text Microbiology 1948 Microbiology 0322 University of Illinois at Urbana-Champaign Dissertation Ph.D. PHD:Microbiology -UIUC 10KS0322PHD