Urease operon in clinical isolates. Ethidium bromide stained agarose gels showing amplicons of genes in the urease gene cluster as noted on the left. Lanes a through j, amplicons from COPD sputum isolates 6P8H1, 14P14H1, 24P17H1, 27P5H1, 33P18H1, 43P2H1, 55P3H1, 66P33H1, 74P16H1, 91P18H1, respectively. Lanes k through t, middle ear fluid aspirate isolates 1749, 1826, 6699, 6700, 4R, 17R, 26R, 47R, P86, P113, respectively. Molecular size standards are noted on the right in kilobases.