3.13.1.4	purified recombinant apoenzyme and enzyme in complex with the CoA moiety from the substrate analogue succinyl-CoA, hanging drop vapour diffusion, mixing of 0.002 ml of 10 mg/ml protein in 50 mM Tris-HCl, pH 7.4, with 0.002 ml of reservoir solution containing 0.1 M Bis-Tris, pH 6.5, and 5-20% PEG 3350, in the absence or presence of 4 mM succinyl-CoA, X-ray diffraction structure determination and analysis at 1.89 A and 2.30 A resolution, respectively, molecular replacement using the monomer of an acyl-CoA dehydrogenase (Acd) from Thermus thermophilus HB8 as search model