Characterization and molecular cloning of a glutathione S-transferase genefrom the tick, Boophilus microplus (Acari : Ixodidae)

A glutathione S-transferase (GST) was purified from the larval cattle tick, Boophilus microplus (Acari: Ixodidae), by glutathione-affinity chromatogra phy. The purified enzyme appeared as a single band on SDS-PAGE and has a mo lecular mass of 25.8 kDa determined by mass spectrometry. The N-terminus of the purified enzyme was sequenced. The full-length cDNA of the enzyme was isolated by RT-PCR using degenerate oligonucleotides derived from the N-ter minal amino acid sequence. The cDNA contains an open reading frame encoding a 223-amino-acid protein with the N-terminus identical to the purified GST . Comparison of the deduced amino acid sequence with GSTs from other specie s revealed that the enzyme is closely related to the mammalian mu class GST . (C) 1999 Elsevier Science Ltd. All rights reserved.