Structure of dihydrodipicolinate synthase mutant Thr44Ser at 1.7 A.

Specificity versus catalytic potency: The role of threonine 44 in Escherichia coli dihydrodipicolinate synthase mediated catalysis.

Drops contained: protein solution (~5 mg mL-1 in Tris.HCl 20 mM, pH 8, 2.5 uL), precipitant (K2HPO4 1.8 M, pH 10, 1.2 uL), and N-octyl-beta-R-glucopyranoside (6% w/v, 0.6 uL). Crystals appeared after 3-5 days and grew to dimensions of up to 0.2 mm., VAPOR DIFFUSION, HANGING DROP, temperature 280K

HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS
1XYC, with residue 44 in each chain removed.

The biological unit is a tetramer generated from the dimer. -X,-X+Y,1/3-Z