DEPHOSPHORYLATION OF ORGANIC PHOSPHORUS COMPOUNDS BY SOIL CATALYSTS

Abstract

Ca-glycero-phosphate when incubated at pH 4 and 45[degree]C in toluene-treated soil underwent 66% mineralization in 18 hrs. from an initial cone, of 210 ppm. of organic P. Dephosphorylation of nucleic acid by soil catalysts. (Ames fine sandy loam) was only about -J- as rapid as the breakdown of Ca-glyccrophosphate when optimum conditions for the respective systems were maintained. The optimal reaction (pH 6.2-7) and temperature (about 60[degree]C) for the dephosphorylation of nucleic acid by soil catalysts were about the same as the optimums which had been previously reported for the root-borne nuclease system. The similarity in the activity curves of these systems (soil catalysts and root-borne enzymes) was suggested as evidence that the catalytic properties of soil may originate in part from residues of plant roots. The rapid catalytic hydrolysis of organic phosphates would affect the penetration and distribution of these materials when added to soil.