CRYSTALLIZATION, PRELIMINARY-X-RAY ANALYSIS AND PATTERSON SEARCH OF ANEW ASPARTIC PROTEASE ISOLATED FROM HUMAN URINE

Aspartic protease (EC 3.4.23) make up a widely distributed class of en zymes in animals, plants, microbes and, viruses. In animals these enzy mes perform diverse functions, which range from digestion of food prot eins to very specific regulatory roles. In contrast the information ab out the well-characterized aspartic proteases, very little is known ab out the corresponding enzyme in urine. A new aspartic protease isolate d from human urine has been crystallized and X-ray diffraction data co llected to 2.45 Angstrom resolution using a synchrotron radiation sour ce. Crystals belong to the space group P2(1)2(1)2(1) The cell paramete rs obtained were a=50.99, b=75.56 and c=89.90 Angstrom. Preliminary an alysis revealed the presence of one molecule in the asymmetric unit. T he structure was determined using the molecular replacement technique and is currently being refined using simulated annealing and conjugate gradient protocols.