EFFICACY OF FILTER TYPES FOR DETECTING CAMPYLOBACTER-JEJUNI AND CAMPYLOBACTER-COLI IN ENVIRONMENTAL WATER SAMPLES BY POLYMERASE CHAIN-REACTION

A previously developed polymerase chain reaction (PCR) amplification o f a target region in the flaA Campylobacter flagellin gene was evaluat ed and adapted for use with environmental water samples. The ability t o detect Campylobacter jejuni or Campylobacter coli in seeded water sa mples was tested with various filters after concentration and freeze-t haw lysis of the bacterial cells. A nonradioactive probe for the ampli fied flagellin gene fragment detected as little as 1 to 10 fg of genom ic DNA and as few as 10 to 100 viable C. jejuni cells per 100 ml of wa ter filtered onto Fluoropore (Millipore Corp.) filters. No amplificati on was obtained with cellulose acetate filters, most likely because of binding of the DNA to the filter. Concentration and lysis of target c ells on Fluoropore and Durapore (Millipore Corp.) filters allowed PCR to be performed in the same reaction tube without removing the filters . This methodology was then adapted for use with environmental water s amples. The water supply to a broiler chicken production farm was susp ected as the source of C. jejuni known to be endemic in grow-out flock s at the farm, despite the inability to culture the organisms by stand ard methods. The filtration-PCR method detected Campylobacter DNA in m ore than half of the farm water samples examined. Amplified campylobac ter DNA was not detected in small volumes of regional surface water sa mples collected on a single occasion in February. The filtration-PCR a mplification method provided a basis for detection of C. jejuni and C. coli in environmental waters with a high degree of specificity and se nsitivity.