Detection of Escherichia coli O157:H7 using immunomagnetic capture and luciferin-luciferase ATP measurement

A procedure for rapid assay (about 30 min) of viable Escherichia coli O157:H7 in solutions is described. The bacteria,captured by specific immunomagnetic beads, were lysed by commercially available reagents. The released cellular ATP was determined by the chemiluminescence method using firefly lantern extracts. The ATP content of the E. coli capable of consuming oxygen was influenced by the presence of glucose. The immunomagnetic procedure was applied to determine the presence of E. coli O157:H7 in beef hamburger spiked with the bacteria. After a 6-h enrichment at 37 degrees C, significant ATP luciferin-luciferase bioluminescence was detected from beef hamburger suspensions spiked with less than one CFU/ml of the E. coli. Possible utilization of the developed procedure for practical application is discussed. Published by Elsevier Science Ltd.