The report, first and foremost, represents a record of the genes that make up the genome of the organism, and the establishment, where possible, of their functions. A surprising number of the genes, Blattner said, are new.

The work also details the similarity between every gene of E. coli and every gene of every other completely sequenced organism. The comparison, according to Blattner, shows that some genes appear commonly throughout nature while others are unique to E. coli. Such information is essential to any understanding of how E. coli and other bacteria have evolved, and what genes are required at a minimum to create life.

In addition to the base order of the chemical building blocks that make up the E. coli genome, and a better sense of its evolution and relationship to other organisms, the work of Blattner's team has yielded a lode of new information about the organization of E. coli genes and how the information stored there is distributed.

It was noticed, too, that some of the DNA may have been added within the recent evolutionary history of the microbe. This immigrant DNA, said Blattner, is seemingly related to the genes of bacteria that cause disease, fueling speculation that the K-12 strain of E. coli has relics of a pathogenic past or, alternatively, is a pathogen waiting to happen.

The E. coli strain used in the Wisconsin study does not cause disease, but related strains are toxic and have been implicated in an increasing number of human food poisonings from products ranging from ground beef to unpasteurized apple juice to fecally contaminated lettuce. With the K-12 E. coli genome in hand, Blattner said it will soon be possible to make a gene by gene comparison with its pathogenic relatives and illuminate genes that govern the toxic nature of the bacte
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Contact: Terry Devitt
trdevitt@facstaff.wisc.edu
608-262-8282
University of Wisconsin-Madison
3-Sep-1997