MOLECULAR CHARACTERIZATION OF HUMAN AND MOUSE FATTY-ACID AMIDE HYDROLASES

Recently, we reported the isolation, cloning, and expression of a rat enzyme, fatty acid amide hydrolase (FAAH), that degrades bioactive fat ty acid amides like oleamide and anandamide to their corresponding aci ds, thereby serving to terminate the signaling functions of these mole cules, Here, we report the molecular characterization of both a mouse and a human FAAH and compare these enzymes to the rat FAAH, The enzyme s are well conserved in primary structure, with the mouse and rat FAAH s sharing 91% amino acid identity and the human FAAH sharing 82% and 8 4% identity with the rat FAAH and mouse FAAH, respectively, In additio n, the expressed human and rat FAAHs behave biochemically as membrane proteins of comparable molecular size and show similar, but distinguis hable, enzymological properties. The identification of highly homologo us FAAH proteins in rat, mouse, and human supports a general role for the fatty acid amides in mammalian biology.