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Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

2002

Electronic Theses and Dissertations

Articles 1 - 2 of 2

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Analysis Of Protistan Grazing On Bioremediative Bacteria Using In Wvo Fluorescent Protein Expression And Flow Cytometry, Yutao Fu Dec 2002

Analysis Of Protistan Grazing On Bioremediative Bacteria Using In Wvo Fluorescent Protein Expression And Flow Cytometry, Yutao Fu

Electronic Theses and Dissertations

Protistan bacterivory can influence the size distribution, cell structure and composition of natural bacterial communities and is of significant concern for design of bioremediation efforts, yet adequate methods for observation and modeling are lacking. In this investigation, fluorescent protein expression and flow cytometry were used to study protistan grazing on genetically modified strains of several bacterial species that have been considered for use in bioremediation. Broad-host-range plasmids were constructed and used to introduce genes encoding GFP (green fluorescent protein) or RFP (red fluorescent protein) to prey species. A heterotrophic flagellate Paraphysomonas imperforata (Hflag) served as a model predator. Predator-prey interactions ...


Critical Amino Acids Of The Gα2 Subunit Helical Domain In Dictyostelium Discoideum, Steven Martin Rauch Dec 2002

Critical Amino Acids Of The Gα2 Subunit Helical Domain In Dictyostelium Discoideum, Steven Martin Rauch

Electronic Theses and Dissertations

In Dictyostelium discoideum organism, the Gα2 subunit of the heterotrimeric G-protein signaling complex plays a pivotal role during the aggregation stage in the Dictyostelium life cycle. The biochemical functions of the G-protein complex include separation of the G-protein coupled receptor from the G-protein subunits, GDP displacement by GTP in the Gα subunit, separation of the Gα monomer from the βγ complex, GTP hydrolysis to GDP, activation of adenylyl cyclase as a downstream effector, and activation of guanylyl cyclase as a separate downstream effector. Upon release from the heterotrimer, the βγ subunits lead to downstream activation of the membrane bound adenylyl ...