[Isolation and properties of tripolyphosphatase from Neurospora crassa].
Homogenous preparation of tripolyphosphatase from Neurospora crassa is obtained. The enzyme is found to consist of two equal subunits with molecular weight of 40 000 and to have pH optimum 7.0 and temperature optimum 50 degrees C. Bivalent metal ions are required for its catalytical activity, the hest activators being Co2+, Mg2+ and Mn2+. Strict specificity of the enzyme to tripolyphosphate is demonstrated, Km being 5.9-10(-4) M. The enzyme hydrolyses tripolyphosphate to equimolar mixture of ortho- and pyrophosphate. The enzyme activity depends on orthophosphate and pyrophosphate concentrations in the incubation medium.
D017766:Acid Anhydride Hydrolases; D002413:Cations, Divalent; D004789:Enzyme Activation; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D046911:Macromolecular Substances; D008970:Molecular Weight; D009491:Neurospora / Q000201:enzymology*; D009492:Neurospora crassa / Q000201:enzymology*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D013329:Structure-Activity Relationship
D002413:Cations, Divalent; D046911:Macromolecular Substances; D010744:Phosphoric Monoester Hydrolases; D017766:Acid Anhydride Hydrolases; C023193:tripolyphosphatase
Vydelenie i svoistova tripolifosfatazy griba Neurospora crassa