The Glutamic Acid of Tumour Proteins

Abstract

IN a recent paper, Kögl and Erxleben¹ record some interesting observations which suggest that the proteins of malignant tissues are partially ‘racemized’. From several normal tissues they were able to isolate, after short acid hydrolysis, relatively good yields of the usual l(+) glutamic acid, showing, in 9 percent hydrochloric acid, the normal rotation of [α]_D + 31.6°, whereas the products isolated from an ovarian tumour, an ovarian carcinoma and from two different mammary carcinomas showed rotations of [α]_D + 21.8°, + 4.6°, + 11.6° and + 16.1°, suggesting that they contained 15.6, 42.7, 31.7 and 24.6 per cent respectively of d(—) glutamic acid. The importance of these findings needs no emphasis, and confirmation in other laboratories is clearly desirable.