Stage-Dependent Protein Composition in the Life Cycle of Synchronous Ichthyophthirius multifiliis,a Ciliate Fish Parasite1

The sequential development of Ichthyophthirius multifiliis Fouquet, 1876 at 22°C was monitored from detachment from the fish through to infective tomites using one-dimensional polyacrylamide gel electrophoresis. Methods are described for synchronizing I. multifiliis cells to permit the collection of large numbers of cells at stages during mitotic division. The electrophoretic protein patterns of the encysted stage differ from those of the tomite stage as well as from those of the other measured intervals.