A METABOLITE OF HALOTHANE COVALENTLY BINDS TO AN ENDOPLASMIC-RETICULUM PROTEIN THAT IS HIGHLY HOMOLOGOUS TO PHOSPHATIDYLINOSITOL-SPECIFIC PHOSPHOLIPASE C-ALPHA BUT HAS NO ACTIVITY

When the inhalation anesthetic halothane was administered to rats, a 58 kDa protein in the liver became covalently labeled by the trifluoroacetyl chloride metabolite of halothane. The amino acid sequences of the N-terminal and of several internal peptide fragments of the protein were 99% homologous to that of the deduced amino acid sequence of a cDNA reported to correspond to phosphatidylinositol-specific phospholipase C-α. The purified trifluoroacetylated 58 kDa protein or native 58 kDa protein, however, did not have phosphatidylinositol-specific phospholipase C activity. We conclude that the reported cDNA of phosphatidylinositol-specific phospholipase C-α may encode for a microsomal protein of unknown function. © 1991.