Rats fed a purified diet supplemented with erotic acid (1%) have gross alterations in their lipid metabolism that can be essentially nullified by further supplementation of the diet with adenine sulfate (0.25%), as described in the first paper of this series (1). Accompanying these changes are certain alterations in the metabolism of pyrimidine derivatives, which have been described in an earli...

* The data in this paper have been taken from a thesis presented by Ray Wu to the Graduate School of Arts and Sciences of the University of Pennsylvania in partial fulfilment of the requirements for the degree of Doctor of Philosophy. An abstract of a preliminary report of this work has appeared (1). Aided by a grant from the American Cancer Society, administered by the Committee on Growth of t...

Orotic acid-C1402H, which was required for biological studies being pursued in this laboratory, has been synthesized by the method of Nyc and Mitchell,5 starting with DL-aspartic acid-a-C1402H. The latter was prepared from ethyl malonate-C1402C2H5, as described by Galat.' This orotic acid probably contains the isotopic carbon exclusively in the carboxyl group since it evolves carbon dioxide con...

Interest in the possibilities of utilizing the Ehr lich ascites tumor for studies of the intermediary metabolism of cancer tissues has been greatly stimulated in recent years by the important work of Klein (10) on the morphological and growth characteristics of these cells. Among the obvious advantages of ascites tumors over tumors growing in the solid form is the fact that one can easily obtai...

The effects of nitrogen mustard, Myleran, and x-radiation on the incorporation of isotopic orotic acid, aspartic acid, formaldehyde, adenine, and phosphate into the nucleic acids of the L1210 ascites leukemia are reported. The lack of uniformity in the incorporation pattern following pretreatment with each of the three drugs was considered significant. The treatments could result in stimulation...