ASSIGNMENTS FOR THE MAIN-CHAIN NUCLEAR MAGNETIC RESONANCES AND DELINEATION OF THE SECONDARY STRUCTURE OF THE CATALYTIC DOMAIN OF HUMAN STROMELYSIN-1 AS OBTAINED FROM TRIPLE-RESONANCE 3D NMR EXPERIMENTS

We report the NMR assignments for the main-chain C-13, N-15, and H-1 resonances ((HN)-H-1, H-1alpha, N-15alpha, C-13alpha, (CO)-C-13) for the 19.5-kDa catalytic domain of human stromelysin-1, a zinc endoproteinase thought to be involved in pathologic tissue degradation. The assignments were predominantly obtained from triple-resonance three-dimensional NMR experiments using double-labeled (N-15/C-13) samples. The secondary structure of the molecule was determined from analysis of 3D N-15-resolved NOESY experiments. It was found to consist of a rive-stranded mixed beta-sheet with four parallel and one antiparallel strand and three helices. The topological arrangement of the secondary structure elements of stromelysin catalytic domain is remarkably similar to that found for astacin, a Zn proteinase for which the tertiary structure was recently determined from X-ray diffraction data [Bode et al. (1992) Nature 358, 164-167].