Molecular analysis of a consortium of ruminal microbes that detoxify pyrrolizidine alkaloids.

TitleMolecular analysis of a consortium of ruminal microbes that detoxify pyrrolizidine alkaloids.
Publication TypeJournal Article
Year of Publication2005
AuthorsLodge-Ivey SL, Rappe MS, Johnston WH, Bohlken RE, Craig AM
JournalCanadian journal of microbiology
Volume51
Issue6
Pagination455-65
Date Published2005 Jun
ISSN0008-4166
KeywordsAnimals, Bacteria, Anaerobic, Polymerase Chain Reaction, Polymorphism, Restriction Fragment Length, Pyrrolizidine Alkaloids, RNA, Bacterial, RNA, Ribosomal, 16S, Rumen, Senecio, Sheep, Species Specificity
Abstract

Members of a consortium of bacteria, isolated from the rumen of sheep, that degrades pyrrolizidine alkaloids (PAs) found in tansy ragwort (Senecio jacobaea) were characterized. An enrichment of ruminal bacteria was isolated from a sample of ruminal fluid using standard anaerobic techniques. The PA degradative capacity of the enrichment was tested by spiking purified PA extract from tansy ragwort. Length heterogeneity analysis by PCR (LH-PCR) and restriction fragment length polymorphism (RFLP) analysis was used to identify members of the consortium. Phylogenetic analysis of the 16S rDNA gene revealed differing results based on the molecular method used. LH-PCR identified 7 different organisms in 3 groups while RFLP identified 6 organisms with differing banding patterns in 5 groups. After the phylogenetic analyses of both methods were combined, the combined isolates represented 6 groups. The majority of the members of this consortium are <97.0% homologous with known bacteria, indicating this consortium may contain novel organisms able to detoxify PAs found in tansy ragwort. Further understanding of the metabolic pathways used by this consortium to degrade PAs could lead to the use of the consortium as a probiotic therapy for livestock and horses afflicted with tansy ragwort toxicosis.

Alternate JournalCan. J. Microbiol.