PutA with the following ligands bound in the GSALDH active site: NADH, D-proline, trans-4-hydroxy-D-proline, cis-4-hydroxy-D-proline, L-proline, and trans-4-hydroxy-L-proline, sitting drop vapor diffusion method, using 19% (w/v) PEG-3350, 0.2 M ammonium sulfate, 0.1 M magnesium chloride, 0.1 M HEPES (pH 8.0), and 0.1 M sodium formate
purified ZmALDH12 in complex with NAD+, sitting drop vapour diffusion method, mixing of 2 mg/ml protein in 50 mM Tris, pH 7.8, 50 mM NaCl, 0.5 mM tris(2-caboxyethyl)phosphine (TCEP), 1 mM NAD+, and 5% v/v glycerol with a crystallization solution containing 0.09 M sodium nitrate, sodium phosphate, and ammonium sulfate, and a precipitant mixture containing 25% v/v 2-methyl-2,4-pentanediol, 25% w/v PEG 1000, and 25% w/v polyethylene glycol 3350, and 0.1 M Tris/bicine pH 8.5, in a 1:1 ratio v/v, X-ray diffraction structure determination and analysis at 2.20 A resolution, structure modeling using molecular replacement and a search model derived from a betaine ALDH (PDB ID 4MPY)