THE CRYSTAL-STRUCTURE OF APO-PSEUDOAZURIN FROM ALCALIGENES-FAECALIS S-6

The 3D structure of the apo-pseudoazurin (copper free pseudoazurin) fr om Alcaligenes faecalis strain S-6 is determined and refined at pH 6.7 using X-ray diffraction data to 1.85 Angstrom resolution. The final c rystallographic R-factor is 0.164. Comparing the structures of apo-pse udoazurin and the native (CU2+) protein, we observed limited differenc es ranging between 0.1-0.4 Angstrom at the vicinity of the copper site , at the loops connecting the secondary structural elements, at certai n beta-strands and at the amino and carboxy termini of the protein.