212 S. MIYACHI, T. HIROKAWA, H. TAMIYA 



probably be related to the CO2 outburst observed by Emerson and 

 Lewis (7) and to the lag of CO2 uptake occurring at the beginning of 

 illumination, which was observed by McAlister and Myers (8-10), 

 Aufdemgarten (11, 12), and van der Veen (13, 14). These authors 

 have also observed that when light was turned off after prolonged 

 illumination there occurred a "gulp" of CO2 or a lag of CO2 produc- 

 tion, which may be accounted for by the temporary increase of back- 

 ground C02-fixing capacity occurring immediately after the transi- 

 tion from light to dark. The fact that the background C02-fixing 

 capacity is largely influenced by light may be taken as an evidence for 

 its being related directly or indirectly to the mechanism of normal 

 photosynthesis. 



Acknowledgment. The experiments reported here were assisted by grants 

 from the Ministry of Education and from the Rockefeller Foundation. The 

 authors are grateful for the advice of Dr. A. H. Brown in the preparation 

 of this paper. 



References 



1. Calvin, M., and Benson, A. A., Science, 107, 476 (1948). 



2. Benson, A. A., Calvin, M., Haas, V. A., Aronoff, S., Hall, A. G., Bassham, 



J. A., and Weigl, J. W., "C" in photosjmthesis," in Photosynthesis in 

 Plants, J. Franck and W. E. Loomis, eds., p. 381. Iowa State College Press, 

 Ames, 1949. 

 :i Tamiya, H., Miyachi, S., and Hirokawa, T., "Some new observations in 

 preillumination experiments using Carbon 14," in this volume, p. 213. 



4. Miyachi, S., Izawa, S., and Tamiya, H., J. Biochem. (Japan), 4^, 221 (1955). 



5. Brown, A. H., Fager, E. W., and Gaffron, H., "Kinetics of a photochemical 



intermediate in photosynthesis," in Photosynthesis in Plants, J. Franck and 

 W. E. Loomis, eds., p. 403. Iowa State College Press, Ames, 1949. 



6. Brown, A. H., Fager, E. W., and Gaffron, H., Arch. Biochem., 19, 407 (1948). 



7. Emerson, R., and Lewis, C. M., A7n. J. Botany, 28, 789 (1941). 



8. McAlister, E. D., J. Gen. Physiol., 22, 613 (1939), 



9. McAUster, E. D., and Myers, J., Smithsonian Misc. Collections, 99, No. 6, 1 



(1940). 



10. McAUster, E. D., and Myers, J., Science, 92, 241 (1940). 



11. Aufdemgarten, H., Planta, 29, 643 (1939). 



12. Aufdemgarten, H., Planta, SO, 343 (1939). 



13. van der Veen, R., Physiol. Plantarum, 2, 217 (1949). 



14. van der Veen, R., Physiol. Plantarum, 2, 287 (1949). 



