Cell surface glycoconjugates control the activity of the NADH-ascorbate free radical reductase of rat liver plasma membrane.
Plasma membrane isolated by two-phase partition from rat liver showed rates of ascorbate free radical reduction by NADH of 4-5 nmoles of oxidized NADH/min/mg protein. This activity was inhibited 80% by ConA and up to 97% by WGA and LFA lectins. NADH-ascorbate free radical reductase was also inhibited in rat liver plasma membranes preincubated with neuraminidase or trypsin, but no additional inhibition was observed in the presence of LFA after enzyme digestion. It appears that the integrity of glucan moieities of the cell surface glycoconjugates are necessary for the optimal function of this activity that could be considered as part of the transplasma membrane electron transport system.
Navas
P
P
Departamento de Biologia Celular, Facultad de Ciencias, Universidad de Córdoba, Spain.
Estévez
A
A
Burón
M I
MI
Villalba
J M
JM
Crane
F L
FL
D000818:Animals; D002462:Cell Membrane / Q000201:enzymology / Q000502:physiology*; D006001:Glycoconjugates / Q000502:physiology*; D007700:Kinetics; D037102:Lectins / Q000494:pharmacology; D008099:Liver / Q000201:enzymology; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism*; D009439:Neuraminidase / Q000494:pharmacology; D051381:Rats
D006001:Glycoconjugates; D037102:Lectins; D009247:NADH, NADPH Oxidoreductases; C023927:monodehydroascorbate reductase (NADH); D009439:Neuraminidase