[I87E mutation prevents barstar dimerization].
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.
Korchuganov
D S
DS
Shul'ga
A A
AA
Ermoliuk
Ia S
IaS
Mit'kevich
V A
VA
Reĭbarkh
M Ia
MIa
Nol'de
S B
SB
Makarov
A A
AA
Arsen'ev
A S
AS
Kirpichnikov
M P
MP
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*
D001426:Bacterial Proteins; C057438:barstar protein, Bacillus amyloliquefaciens; D012260:Ribonucleases; C019760:Bacillus amyloliquefaciens ribonuclease