NTP binding and phosphohydrolase activity associated with purified bluetongue virus non-structural protein NS2.
The bluetongue virus ssRNA-binding protein, NS2, is a phosphoprotein that forms viral inclusion bodies in infected cells. Recombinant NS2 was expressed in the baculovirus expression system and purified to homogeneity from insect cells. Purified NS2 bound nucleosides. Further investigation revealed that the protein bound ATP and GTP and could hydrolyse both nucleosides to their corresponding NMPs, with a higher efficiency for the hydrolysis of ATP. The increased efficiency of hydrolysis of ATP correlated with a higher binding affinity of NS2 for ATP than GTP. Ca(2+), Mg(2+) and Mn(2+) were able to function as the required divalent cation in the reactions. The phosphohydrolase activity was not sensitive to ouabain, an inhibitor of cellular ATPases, suggesting that this activity was not the result of a cellular contaminant.
Horscroft
Nigel J
NJ
NERC Institute of Virology and Environmental Microbiology, Mansfield Road, Oxford OX1 3SR, UK2.|Department of Biochemistry, Oxford University, Oxford OX1 3QU, UK1.
Roy
Polly
P
Department of Geographic Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA3.|NERC Institute of Virology and Environmental Microbiology, Mansfield Road, Oxford OX1 3SR, UK2.|Department of Biochemistry, Oxford University, Oxford OX1 3QU, UK1.
D000255:Adenosine Triphosphate / Q000378:metabolism*; D001820:Bluetongue virus / Q000737:chemistry*; D006160:Guanosine Triphosphate / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D017361:Viral Nonstructural Proteins / Q000378:metabolism*
D017361:Viral Nonstructural Proteins; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D010744:Phosphoric Monoester Hydrolases