[Catalytic characteristics of 5'-nucleotidase in the structure of cell membrane rafts in smooth muscles].
5'-nucleotidase (EN 3.1.3.5) is widely distributed enzyme occurring in vertebrate, bacterial and plant cells. The main physiological function of 5'-nucleotidase is hydrolysis of 5'-AMP to adenosine and Pi. It was found that the detergent-insoluble membrane domains (rafts) are enriched by proteins possessing high 5'-AMPase activity. This study is aimed to investigate some physical and chemical properties of 5'-nucleotidase, which is present in detergent insoluble membrane domains isolated from pig stomach and lung. It was shown for the first time that catalytic properties of the raft-associated 5'-nucleotidase and of the pure enzyme described in literature differ. Our results demonstrate that the greatest activity of the raft-associated enzyme takes place in the physiological conditions contrary to the pure enzyme. Our data suggest that such changes of 5'-nucleotidase catalytic activity might be due to the disruption of its interaction with membrane rafts.
Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Taras Shevchenko Kyiv National University, Kyiv. valdan@biochem.kiev.ua
V M
VM
Danylova
O V
OV
Andrukhova
V S
VS
Babiĭchuk
O Ia
OIa
Andrukhov
E B
EB
Babiĭchuk
D015720:5'-Nucleotidase / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D002384:Catalysis; D066298:In Vitro Techniques; D008168:Lung / Q000201:enzymology; D021962:Membrane Microdomains / Q000201:enzymology*; D009130:Muscle, Smooth / Q000201:enzymology*; D013270:Stomach / Q000201:enzymology; D013379:Substrate Specificity; D013552:Swine
D015720:5'-Nucleotidase