ATOMIC-RESOLUTION STRUCTURE OF CONCANAVALIN-A AT 120 K

The structure of native concanavalin A has been refined to a resolutio n of 1.2 Angstrom, against data collected at 120 K. The space group is I222, with a=61.954(8), b=86.053 (11), c=89.079(11) Angstrom. The str ucture was refined by restrained weighted least-squares minimization o f Sigma w(F-o(2)-F-c(2))(2) with SHELXL92/3/6. The final model contain s all of the atoms from 237 amino acids, two metal ions and 271 water molecules spread over 287 sites. Disorder is modelled over two conform ations for 30 amino-acid side chains. The final weighted R index on F- 2 (wR(2)) On all data was 30.4%. Conventional R indices based on F wer e 14.2 and 11.8% for all data and for data with F > 4 sigma(F), respec tively.