Specificity and sensitivity of the primer pair fps158 and rps743minus4 with chromosomal DNA of the P. stutzeri type strain (a) and the P. alcaligenes type strain (b). The amounts of template DNA were approximately 5 × 105 (lane 2), 5 × 104 (lane 3), 5 × 103 (lane 4), 5 × 102 (lane 5), 50 (lane 6), and 5 genome equivalents (lane 7). The PCR product was 625 bp. Lane 1 contains molecular weight markers (Smart Ladder; Eurogentec).