Escherichia coli O157:H7 is a bacterium
that has caused great concern in the meat and
food industry during the last few years
because of several, well-publicized, disease
outbreaks, including the incident at the Jack-in-
the-Box fast food chain in Seattle, Washington.
The organism can cause severe
sickness and even death in certain population
groups. To better assure meat safety, federal
meat inspection is focusing on developing
rapid methods to detect this disease agent
and others. Oxyrase is a commercially available
enzyme that can accelerate the growth of
some bacteria. Current techniques for
isolation and culturing of E. coli O157:H7
from foods require an enrichment period of
18 to 24 hours, thus limiting their usefulness
for perishable foods that are marketed quickly.
Our investigation found that Oxyrase
shortened required enrichment periods in
broth culture only. The enzyme was less
effective in sterilized ground beef.