title: Purification, crystallization, and preliminary x-ray diffraction studies of the flavoenzyme mercuric ion reductase from Bacillus sp. strain RC607.
abstract: The flavoenzyme mercuric ion reductase from Bacillus sp. strain RC607 was purified by dye-ligand affinity chromatography. The protein was crystallized from solutions of high ionic strength, and one of the two crystal forms obtained has proven suitable for x-ray diffraction studies. Preliminary analysis showed that these crystals belong to the tetragonal space group 1422. The unit cell dimensions are a = b = 180.7 A; c = 127.9 A. The diffraction pattern extends to better than 3 A resolution. Crystal density measurements are consistent with one enzyme dimer of 2 x 69,000 Da comprising the asymmetric unit. Trypsin treatment of the native enzyme resulted in the removal of 157 amino acids at the N terminus. After purification, the remaining fragment (amino acids 158-631), which is still fully active in vitro, could be crystallized under the same conditions as native enzyme. Twinning problems, however, did not allow complete analysis of these crystals.
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: M J
authors.initials: MJ
authors.lastname: Moore
authors.forename: M D
authors.initials: MD
authors.lastname: Distefano
authors.forename: C T
authors.initials: CT
authors.lastname: Walsh
authors.forename: N
authors.initials: N
authors.lastname: Schiering
authors.forename: E F
authors.initials: EF
authors.lastname: Pai
mesh_terms: D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins / Q000302:isolation & purification*; D003460:Crystallization; D004926:Escherichia coli / Q000235:genetics; D005822:Genetic Vectors; D006868:Hydrolysis; D008970:Molecular Weight; D010088:Oxidoreductases / Q000302:isolation & purification*; D014357:Trypsin; D014961:X-Ray Diffraction
chemical_list: D001426:Bacterial Proteins; D010088:Oxidoreductases; C021551:mercuric reductase; D014357:Trypsin