Regulation of the GM1-galactosidase supramolecular structure and catalytic activity in vitro.
Regulation of the supramolecular organization and the catalytic activity of GM1-galactosidase (EC 3.2.1.23) and neuraminidase (EC 3.2.1.18) from human kidney was studied in a system of hydrated reversed micelles of Aerosol OT in octane. It was shown that both the catalytic activity and the oligomeric structure of the GM1-galactosidase in reversed micelles depend on the [H2O]/[Aerosol OT] molar ratio (w(o)). GM1-galactosidase 64-67 kDa monomers, 260 kDa tetramers, and 660 kDa octamers were obtained in systems with w(o) = 0-20, 25-30 and 30-40, respectively. The association of GM1-galactosidase monomers into an octamer results in the cooperative increase in enzymatic activity. 'Protective protein', a component of the GM1-galactosidase-neuraminidase native complex, was found to improve this association significantly.
Pshezhetsky
A V
AV
Belozersky Institute of Physico-Chemical Biology, Moscow State University, Russia.
Levashov
A V
AV
Wiederschain GYa
D006017:Glycolipids / Q000737:chemistry; D006801:Humans; D007668:Kidney / Q000201:enzymology; D008247:Lysosomes / Q000201:enzymology; D008823:Micelles; D009439:Neuraminidase / Q000737:chemistry* / Q000302:isolation & purification; D009795:Octanes; D011487:Protein Conformation; D001616:beta-Galactosidase / Q000737:chemistry* / Q000302:isolation & purification
D006017:Glycolipids; D008823:Micelles; D009795:Octanes; D009439:Neuraminidase; C021502:acid beta-galactosidase; D001616:beta-Galactosidase; C026728:octane