Immunochemical detection of esterases from the cattle tick Boophilus Microplus

Abstract

Rosario-Cruz R, García-Vázquez Z, Edward JG. Téc Pecu Méx 2000,38(3)203-210. An esterase from Boophilus microplus tick strain resistant to organophosphates was detected after SDS-PAGE. The protein showing activity was separated and used as an antigen to produce a polyclonal antibody. The polyclonal antibody was tested in a western blot for specific binding and three different Boophilus microplus tick strains were electrophoretically analyzed. The active protein showed differences in activity favoring the resistant tick strains but did not show any difference in a Western-Blot analysis when the same amount of protein was electrophoretically separated. The isoelectrofocussing however, showed differences in expression of esterase isozymes within a range of isoelectric point from 4.5 to 5.0. The evidences suggest that differences in activity are due to the participation of isoforms which are not immunologically differentiated, since, the Western blot did not show any difference between strains. The presence of isozymes with different physicochemical features, will be of great interest in the diagnosis of resistance to ixodicides, since they can be used as molecular markers for acaricide resistance detection.