[Isolation and primary characterization of two forms of inorganic pyrophosphatase from ox heart muscle mitochondria].

A method allowing to obtain two highly purified forms (membrane-bound and soluble ones) of inorganic pyrophosphatase from bovine heart mitochondria is described. Both forms have the isoelectric point of 5.8, pH optimum with Mg2+ at 7--9, are maximally stable at pH 5.

[ On the absence of high-molecular polyphosphates in chloroplasts of Acetabularia mediterranea].

High-molecular polyphosphates have been identified in a crude fraction of chloroplasts of Acetabularia mediterranea. However, after a short-term treatment of the fraction with a hypotonic salt solution and centrifugation in a sucrose density gradient it was found possible to completely separate high-molecular polyphosphates from intact chloroplasts. Consequently the chloroplasts themselves contain no high-molecular polyphosphates.