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 immunomagne tic beads, were lysed by commercially available reagents. The released cell ular ATP was determined by the chemiluminescence method using firefly lante rn extracts. The ATP content of the E. coli capable of consuming oxygen was influenced by the presence of glucose. The immunomagnetic procedure was ap plied 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 susp ensions spiked with less than one CFU/ml of the E. coli. Possible utilizati on of the developed procedure for practical application is discussed. Publi shed by Elsevier Science Ltd.