AN ABSTRACT OF THE THESIS OF Diane R. Gray for the degree of Master of Science in Microbiology presented February 5, 1998. Title: Bacterial 16S Ribosomal DNA Analysis of Pyrrolizidine Alkaloid Detoxifying Enrichments from the Ovine Rumen

approved: A. Morrie Craig N Bacterial cultures enriched from sheep rumen fluid have demonstrated the ability to detoxify pyrrolizidine alkaloids (seneciphylline and jacobine) in tansy ragwort (Senecio jacobaea). The microbes are difficult to isolate using classical anaerobic techniques, therefore, microbes from two different enrichment cultures demonstrating similar degradation activity were identified using their 16S ribosomal RNA genes. Gene sequences from a rich medium enrichment were matched to Clostridium bifermentans, Prevotella ruminicola, Escherichia coif, and from a minimal medium enrichment to, C. clostridiiforme, C. aminophilum, Streptococcus bovis, and Butyrivibrio fibrosolvens. There were no identical organisms between the two libraries, but the common genus was Clostridium. Redacted for Privacy ©Copyright by Diane R. Gray February 5, 1998 All Rights Reserved BACTERIAL 16S RIBOSOMAL DNA ANALYSIS OF PYRROLIZIDINE ALKALOID DETOXIFYING ENRICHMENTS FROM THE OVINE RUMEN