Purification and Characterization of a Major Kyotorphin-Hydrolyzing Peptidase of Rat Brain

摘要: We purified a major kyotorphin (L-Tyr-L-Arg)-hydrolyzing peptidase (KTPase) from the rat brain, to electrophoretic homogeneity using conventional chromatographic techniques. KTPase was 1,660-fold with specific activity of 161 mumol/min/mg protein and 6.8% recovery. The enzyme composed single polypeptide molecular mass 67 kDa an isoelectric point (pI) 5.5. has ability hydrolyze variety natural dipeptides. It also liberated NH2-terminal tyrosine Tyr-Gly-Gly Tyr-Tyr-Leu. Bestatin arphamenine B were potent inhibitors this enzyme, while amastatin puromycin had little effect. An excess anti-KTPase antibody raised in white rabbit precipitated approximately 80% kyotorphin-hydrolyzing cytosol brain. These data suggested that role degradation within neuronal cells