The effect of protease inhibitors on degradation of GAM56 in Eimeria tenella gametocytes. A sample of purified E. tenella gametocytes was lysed and equal volumes of lysate added to a range of protease inhibitors (see Table 3 for details on concentrations and specificity) or PBS. A zero time point sample was taken immediately. Other samples were incubated for 24 h at 37°C, after which the assay was halted by addition to Laemmli buffer and the samples subjected to SDS-PAGE and immunoblotting as described previously [20, 21] to assess the disappearance of GAM56. Lane 1, time = zero sample; Lane 2, pepstatin A; Lane 3, E64; Lane 4, aprotonin; Lane 5, AEBSF; Lane 6, bestatin; Lane 7, leupeptin; Lane 8, phosphoramidon; Lane 9, EDTA; Lane 10, a cocktail of pepstatin A, E64, aprotonin, AEBSF, bestatin, leupeptin, phosphoramidon and EDTA; Lane 11, control sample containing no protease inhibitors.