FIG. 6.

Differentiation of live C. parvum oocysts from heat-killed oocysts (Δ) and oocysts inactivated by long-term storage at room temperature (aged) using CryptoPMA-PCR. Live (lanes 2, 3, 9, and 10), heat-killed (lanes 4, 5, 11, and 12), and aged (lanes 6, 7, 13, and 14) C. parvum oocysts were incubated with 150 μM PMA for 5 min and then exposed to light for 2 min (lanes 3, 5, 7, 10, 12, and 14). Genomic DNA was purified as described in Materials and Methods. SSU rRNA gene PCR amplicons from DNA equivalent to 100 (A) or 10 (B) live, heat-killed, or aged oocysts were visualized using an Agilent Bioanalyzer 2100. M, marker; −, no PMA; +, PMA added; Δ, treated at 70°C.