Phosphorus in vegetable proteins

Summary

• 1. The albumin and the globulin inLathyrus sativus and the globulin inVicia sativa were prepared by different methods and their properties studied.

• 2. The globulin inLathyrus sativus contains more of histidine and less of arginine than the corresponding protein fromvicia sativa. The tyrosine and tryptophane contents are about the same in all the cases. The albumin fromLathyrus sativus is richer in cystine than the other preparations.

• 3. Fractionation of the globulins ofVicia sativa by increasing salt saturation showed that none of the preparations contained any phosphorus. Small quantities of that element present in preparations obtained by the usual standard methods of dilution or dialysis, especially the latter, are traceable to impurities, adsorbed or otherwise retained by the protein. These and the related observations would suggest that the whole question of “phospho-globulins” of vegetable origin require careful re-enquiry.

• 4. After removal of the globulins (as in 3), a small quantity of a fraction (albumin?) containing 6·7 per cent. of nitrogen and 10 per cent. of phosphorus was obtained. The mode of association of phosphorus with this preparation is under investigation.