METABOLIC ASPECTS 



145 



60 80 100 



MINUTES 



Fig. 3. Oxidation of H2 with fumarate by R. rubrum 

 particles in the presence of redox carriers; light- 

 stimulated catalysis by DPIP. After Bose and Gest 



(61). 



Conditions: Tris-HCl pH 8.0, 150 ^umoles; potas- 

 sium phosphate pH 7.6, 3.5 //moles; sodium fumarate, 

 40^moles; washed R. rubrum particles (fromalurama- 

 ground cells) containing 0.98 mg bacteriochlorophyll; 

 water to make 2.0 ml final volume; 0.2 ml of 20% KOH 

 in center well; gas phase, H2; temperature, 30 C; 

 light intensity, 1000 foot-candles. Redox carriers 

 (approximately 4 //moles) were added at zero time, 

 and fumarate at 55 minutes. Brilliant cresyl blue, 

 BCB; potassium ferricyanide, FeCy. 



