ZN2MG ALKALINE-PHOSPHATASE IN AN EARLY PTOLEMEIC MUMMY

Bone samples of a ptolemeic mummy have been employed to study the mode of conservation on the intactness of Zn2Mg alkaline phosphatase in bo th structure and catalytic activity. A protein of M(r) = 190 +/- 10 kD a being identical to the 200 kDa enzyme of fresh human bones was succe ssfully isolated. Regardless of age 200 kDa protein bands and a distin ct subunit at 60 kDa were seen in SDS-PAGE electrophoresis. The 200 kD a band was also monitored by activity staining. The specific activity was 120 mU/mg and 65% of the respective activity obtained in the ident ical preparation using fresh human tibia or rib. The enzymic activity was inhibited in the presence of 1,10-phenanthroline and L-homoarginin e. Radiocarbon dating supported the assignment of the mummy to the ear ly ptolemeic period. Among the many bactericidal and fungicidal compon ents employed for mummification were aromatic alcohols, mono- and sesq uiterpenes. Pistachio resin was the major balm resin used. The microbi ological sterility of the bone surface was ascertained by independent bacterial and fungal examinations.