Multiple Assemblies exist for SMTL entry 1dr4
CRYSTAL STRUCTURES OF ORGANOMERCURIAL-ACTIVATED CHICKEN LIVER DIHYDROFOLATE REDUCTASE COMPLEXES; X-RAY DIFFRACTION 2.40 Å

	SMTL ID 1dr4.1 Ligands MERCURY (II) ION; CALCIUM ION; NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE; 7,8-DIHYDROBIOPTERIN Polypeptides DIHYDROFOLATE REDUCTASE Oligo-state monomer
	SMTL ID 1dr4.2 Ligands MERCURY (II) ION; CALCIUM ION; NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE; 7,8-DIHYDROBIOPTERIN Polypeptides DIHYDROFOLATE REDUCTASE Oligo-state homo-dimer