Phosphorus Compounds in the Mammary Gland

I. Negative evidence to detect radioactive phosphopeptide in the acid-soluble fraction

Abstract

When studied paper-electrophoretically, the acid-soluble, barium-acetone-insoluble fraction was found to have two ninhydrin-positive bands and one radioactive band. The radioactive band seemed to be of different type from the ninhydrin-positive bands (Fig. 2).
Several ninhydrin-positive substances were detected from that fraction by paper-chromatography (Fig. 3).
The radioactive fraction was clearly separated from the ninhydrin-positive fraction by using ion-exchange column chromatography with DOWEX-2 (OH-type) and eluting with hydrochloric acid (Fig. 4).
Ther adioactive-phosphorus containing fraction was shown to have absorption at 260mμ and some pentoses.
It was concluded that the substance which incorporated 32P specifically was not phospho-peptides, but possibly some kinds of nucleotide.