title: Proteolytic cleavage of gram-positive beta recombinase is required for crystallization.
abstract: Beta recombinase, a DNA resolvase-invertase, catalyzes in the presence of a chromatin-associated protein such as Hbsu, DNA resolution or DNA inversion on supercoiled substrates containing two directly or inversely oriented target (six) sites. Single crystals of the beta recombinase from plasmid pSM19035 were obtained using the vapor diffusion technique with ammonium phosphate as the precipitating agent. The crystals diffracted X-rays to a maximum resolution of 2.5A. Due to proteolytic degradation during the crystallization experiment, the crystals contain only the N-terminal catalytic domain of beta recombinase corresponding to about 60% of the molecular mass of the initially assayed native protein. The proteolytic removal of the C-terminal DNA-binding domain demonstrated that protein modification can be essential to provide material suitable for X-ray analysis.
authors.affiliation: Institut für Kristallographie, Freie Universität Berlin, Takustrabetae 6, 14195 Berlin, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Orth
authors.forename: P
authors.initials: P
authors.lastname: Jekow
authors.forename: J C
authors.initials: JC
authors.lastname: Alonso
authors.forename: W
authors.initials: W
authors.lastname: Hinrichs
mesh_terms: D001665:Binding Sites; D003460:Crystallization; D018360:Crystallography, X-Ray; D004254:DNA Nucleotidyltransferases / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000737:chemistry; D019281:Dimerization; D010450:Endopeptidases; D006094:Gram-Positive Bacteria / Q000201:enzymology; D019426:Integrases; D010446:Peptide Fragments / Q000737:chemistry; D017433:Protein Structure, Secondary; D045522:Recombinases; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013297:Streptococcus pyogenes / Q000201:enzymology
chemical_list: D004268:DNA-Binding Proteins; D010446:Peptide Fragments; D045522:Recombinases; D004254:DNA Nucleotidyltransferases; D019426:Integrases; C115006:integron integrase IntI1; D010450:Endopeptidases