Solving the first globular protein structure: BUSIIIA

BUSI IIA is a 57-residue protease inhibitor. Building on the previously completed sequential assignment, its secondary structure was determined using regular patterns of nuclear Overhauser effects, J-couplings and amide exchange. This was made possible using a number of technical advances, particularly phase-sensitive two-dimensional NMR. Its complete tertiary structure was then determined, using distance geometry to calculate the structure. The calculation was based on NMR-observable parameters only, although in a subsequent appendix to the published paper it was shown that the structure could be markedly improved by energy minimization. Copyright (C) 2003 John Wiley Sons, Ltd.