1.4.99.6	in complex with D-leucine, to 1.07 A resolution. Structure reveals a covalent N(5) flavin adduct, instead of the expected iminoleucine product in the active site. This acyl adduct can be reproduced by photoreduction of the enzyme in the presence of 4-methyl-2-oxopentanoic acid (ketoleucine)	
1.4.99.6	in complex with iminoarginine, to 1.06 A resolution, and in complex with iminohistidine, to 1.3 A resolution. The structure comprises an unliganded conformation and a product-bound conformation. The active site is partially occupied with iminoarginine product that interacts with Tyr53 in the minor conformation of a surface loop. The guanidinium side chain of iminoarginine forms a hydrogen bond interaction with the hydroxyl of Thr50 and an ionic interaction with Glu87. In complex with iminohistidine, two alternate conformations are observed for iminohistidine where the imidazole groups form hydrogen bond interactions with the side chains of His48 and Thr50 and either Glu87 or Gln336. The different interactions and very distinct binding modes observed for iminoarginine and iminohistidine are consistent with the 1000fold difference in kcat/Km values for D-arginine and D-histidine	
1.4.99.6	structure without added D-amino acids, to 1.06 A resolution, and in presence of D-arginine and D-histidine