Protein analysis of Babesia caballi merozoites by two-dimensional polyacrylamide gel electrophoresis and Western blotting

Babesia caballi merozoites were prepared by combining two improved methods of cultivation and purification of merozoites using Percoll-gradiation, and the protein compositions of merozoites were analyzed by two-dimensional so dium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blottin g. The relative molecular masses of the major proteins and protein masses s eparated by electrophoresis were >94, 80-70, 50-45, 34-30, 30-28 and 18 kDa . By Western blotting, twelve proteins or protein groups were recognized by pooled sera from two horses experimentally infected with B. caballi. Among twelve proteins, five new proteins (54, 30-26, 24, and two 18 kDa) were id entified, and the 48 kDa protein was revealed to consist of 2 components in the B. caballi merozoite. One protein (54 kDa) of B. caballi was also reco gnized by the pooled sera from two horses experimentally infected with B. e qui.