Crystallization and preliminary analysis of neurolysin

Neuropeptidases inactivate or modify the activity of peptide neurotransmitters and neurohormones. The neuropeptidase neurolysin acts only on short peptides and accepts a variety of cleavage-site sequences. Structures of the enzyme and enzyme-substrate complexes will help to determine the mechanisms of substrate selectivity used by this enzyme. Crystals of recombinant neurolysin have been grown in the orthorhombic space group P2₁2₁2, with unit-cell parameters a = 157.8, b = 88.0, c = 58.4 Å. Data have been collected to 2.3 Å at 110 K with observed diffraction to 1.8 Å. Circular dichroism measurements suggest that the enzyme is primarily α-helical, with little β-strand secondary structure. Sequence-based secondary-structure prediction supports this conclusion.