THE PATH OF CARBON IN PHOTOSYNTHESIS. XVII. PHOSPHORUS COMPOUNDS AS INTERMEDIATES IN PKOTOSYNTHESIS

Studies of carbon dioxide f ixat ion i n peen plants using the c14 isotope have shown tha t in very short times phosphoglycer5c acid canti~ins most of the r ~ d i o a e t i v i t y ~ 13293 The t racer is present almost en t i re ly ir, the carboql phosphoglyceric aciC can.be seen fron the acccmpanying photographs. rn * she work described in this paper was sponsorec I-;: t h e U. So ritom2.c Energy C o d s s i o n o a f t e r f ive minutes i n radioactive GO2, &my of the phosphates also contaic a carbon label, Even a f t e r s ixty seconds photosynthesis by Chlorella, by fa ^ the WOP par t of the radioactivity is i n the fom of phosphates ( ~ i g u r e (3). Since the discovery of radioactive phosphoglyceric acid as a primaibg. carbayla t ion product, our at tent ion has been directed towards the path by which the radiocarbon becomes converted in to the various c e l l constituents, The ef fec t of numerous external factors on the t o t a l fixation a d on the f ixa t ion pattern, as shown by radioautographs of the two-dimensiona