title: [I87E mutation prevents barstar dimerization].
abstract: The C40,82A;I87E mutant of barstar, an intracellular inhibitor of the ribonuclease barnase from Bacillus amyloliquefaciens, was obtained, and its physicochemical properties were studied. It was produced as a fusion protein with thioredoxin and then cleaved from this by EKmax enterokinase. The mutant was shown by NMR to retain the spatial structure of the wild-type protein but, in contrast to barstar, does not form the homodimers characteristic of barstar in aqueous solution. The mutant protein binds barnase with the dissociation constant (6.6 +/- 1.1) x 10(-11) M and exhibits other physicochemical properties similar to those of the wild-type barstar. This allows the use of C40,82A;I87E mutant instead of wild-type barstar in investigations where the protein dimerization is undesirable. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 6; see also http://www.maik.ru.
authors.forename: D S
authors.initials: DS
authors.lastname: Korchuganov
authors.forename: A A
authors.initials: AA
authors.lastname: Shul'ga
authors.forename: Ia S
authors.initials: IaS
authors.lastname: Ermoliuk
authors.forename: V A
authors.initials: VA
authors.lastname: Mit'kevich
authors.forename: M Ia
authors.initials: MIa
authors.lastname: Reĭbarkh
authors.forename: S B
authors.initials: SB
authors.lastname: Nol'de
authors.forename: A A
authors.initials: AA
authors.lastname: Makarov
authors.forename: A S
authors.initials: AS
authors.lastname: Arsen'ev
authors.forename: M P
authors.initials: MP
authors.lastname: Kirpichnikov
mesh_terms: D001407:Bacillus; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D018360:Crystallography, X-Ray; D019281:Dimerization; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009154:Mutation; D012260:Ribonucleases / Q000037:antagonists & inhibitors*
chemical_list: D001426:Bacterial Proteins; C057438:barstar protein, Bacillus amyloliquefaciens; D012260:Ribonucleases; C019760:Bacillus amyloliquefaciens ribonuclease