687 



William L. Ogren and David W. Krogmann 



the light induced reduction of a part of the coenzyme pool. The reduced 

 forms of the pyridine nucleotides are destroyed by the acid extraction 

 procedure used in these measurements. While efforts to measure the 

 reduced pyridine nucleotide content are as yet incomplete, the data 

 indicate that there is no more than one fourth as much reduced as 

 oxidized coenzyme in the chloroplast fraction. From this, it appears that 

 the steady state levels of reduced pyridine nucleotide and ATP do not 

 differ greatly in light or darkness. 



Acknowledgment: 



This work was supported by a grant (GM-07658) from the United States 

 Public Health Service. 



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