MI009-06 Genomic characterization of E. coli O157:H7 from spinach outbreak - Completed

E. coli O157:H7 has caused large outbreaks of food and water borne disease and contributes to thousands of sporadic cases of illness each year in the U.S. In August of 2006, a large multistate outbreak of O157 illness began that has been associated with consumption of contaminated spinach. In all, 204 cases were reported from 26 states and one case in Canada. Because of the high rate of hospitalization and HUS observed in this outbreak, it has been hypothesized that this particular O157:H7 strain is hyper virulent. To investigate this outbreak strain, we propose to use a new rapid gene sequencing technology to sequence the E. coli O157:H7 strain isolated from a case In Michigan associated with the multistate spinach outbreak. We will also examine and compare global patterns of gene expression of this tsrain with other representative outbreak strains using a multigenome microarray. The results of this project proposed will address gaps in knowledge regarding which factors and genetic traits contribute to the variation in virulence among O157:H7 strains and understanding why some O157 strains cause more serious disease and clinical complications.

Publications:

Analysis of the Genome of the Escherichia coli O157:H7 2006 Spinach-Associated Outbreak Isolate Indicates Candidate Genes That May Enhance Virulence

Deliverables:

* Assembled contigs of the genome sequence (12x to 20x coverage) of an E. coli O157:H7 strain linked to the recent spinach outbreak and recovered from a patient in Michigan.

* List sequences of novel strain-specific genes or single nucleotide polymorphisms found either on the chromosome or on plasmids.

* Compare the patterns of gene expression in the spinach outbreak strain to representative strains from other outbreaks (e.g. Michigan, 1982; Washington, 1993; Japan, 1996) with special attention to Shiga toxin and other genes associated with virulence.