title: [Isolation and catalytic properties of the soluble monomeric form of inorganic pyrophosphatase from baker's yeast].
abstract: Data from sedimentation analysis suggest that modification of about 40% of free amino groups of inorganic pyrophosphatase by maleic anhydride, pH 10.5, results in a loss of the enzyme ability to form dimers at neutral values of pH. The specific activity of monomeric pyrophosphatase is 50-80% of that of the dimeric form. The monomer has a pH optimum of about 7, requires metal ions for activation of both enzyme and substrate and is capable of exergonic synthesis of PPi in the active center. The enzyme binding to PPi is strongly stabilized by fluoride. The experimental data indicate that the individual subunit of inorganic pyrophosphatase possesses all the main catalytic properties of native dimeric molecule.
mesh_terms: D006863:Hydrogen-Ion Concentration; D043564:Inorganic Pyrophosphatase; D007700:Kinetics; D046911:Macromolecular Substances; D011755:Pyrophosphatases / Q000302:isolation & purification / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
chemical_list: D046911:Macromolecular Substances; D011755:Pyrophosphatases; D043564:Inorganic Pyrophosphatase
vernacular_title: Poluchenie i kataliticheskie svoĭstva rastvorimoĭ monomernoĭ formy neorganicheskoĭ pirofosfatazy iz pekarskikh drozhzheĭ.