?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F9638%2F&rft.title=Epidemiologic+and+Mutational+Characteristics+of+Variable-Number+Tandem+Repeats+in+Escherichia+coli+O157%3AH7&rft.creator=Noller%2C+Anna+Christine&rft.description=Escherichia+coli+O157%3AH7+is+an+important+food-borne+pathogen+and+public+health+risk+that+infects+thousands+of+people+a+year+in+the+United+States+alone.+While+many+infections+may+remain+undetected%2C+some+develop+into+hemorrhagic+colitis+and%2For+hemolytic+uremic+syndrome+especially+in+young+children+and+the+elderly.+The+development+of+the+molecular+subtyping+technique+pulsed-field+gel+electrophoresis+(PFGE)+greatly+enhanced+the+detection+of+outbreaks+caused+by+this+organism%2C+but+its+technical+limitations+had+researchers+searching+for+alternative+techniques.+The+use+of+variable-number+tandem+repeats+(VNTRs)+for+human+forensics+and+subtyping+of+extremely+clonal+bacterial+species+such+as+Bacillus+anthracis+provided+a+potential+new+technique+for+examining+E.+coli+O157%3AH7.+This+new+technique%2C+multi-locus+VNTR+analysis+(MLVA)%2C+examines+multiple+VNTR+loci%2C+which+are+some+of+the+most+rapidly+evolving+genetic+elements+in+the+genome.+We+demonstrated+the+utility+and+superiority+of+MLVA+over+PFGE+as+a+molecular+subtyping+technique+for+E.+coli+O157%3AH7.+With+the+establishment+of+the+MLVA+protocol%2C+the+need+arose+to+understand+how+often+the+MLVA+loci+mutate+to+help+characterize+which+isolates+are+highly+related.+Using+an+experimental+protocol+of+10+serial+subcultures%2C+one+of+the+7+MLVA+loci+was+found+to+be+hypervariable+with+a+tendency+of+single%2C+addition+TR+mutation.+Two+other+loci+were+found+to+be+slightly+variable+while+the+remaining+4+loci+had+no+mutation+events+during+the+experiments.+The+establishment+of+a+protocol+based+on+VNTRs+and+the+initial+understanding+of+mutational+dynamics+only+touched+upon+the+genotypic+roles+of+VNTRs+but+not+the+functional+roles.+A+preliminary+examination+of+the+functional+roles+of+a+few+selected+VNTRs+was+undertaken+by+performing+a+variety+of+tests.+A+detailed+description+of+all+this+project's+results+is+presented+in+the+following+work.&rft.date=2004-12-03&rft.type=University+of+Pittsburgh+ETD&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F9638%2F1%2FNollerAC2004.pdf&rft.identifier=++Noller%2C+Anna+Christine++(2004)+Epidemiologic+and+Mutational+Characteristics+of+Variable-Number+Tandem+Repeats+in+Escherichia+coli+O157%3AH7.++Doctoral+Dissertation%2C+University+of+Pittsburgh.++++(Unpublished)++