54 THE BACTERIAL PHOTOCHEMICAL APPARATUS 



RESULTS AND CONCLUSIONS 



All experiments were conducted with Rps. spheroides, strain Ga. 

 Medium B of Sistrom (3) was used. The cultures were aerated with 5% 

 CO2 in N2. A lightintensity of 600fcs was used throughout. Two layers 

 of red cellophane were used as a filter to avoid photoreactions with 

 pigmented inhibitors. Bacteriochlorophyll and neurosporene were 



100 



.8 



.3 



10 



8 ^ 



E 



6 o> 



4i 



OL 

 O 



^ o 



_l 



X 



o 



lU 



\- 



o 

 < 



CD 



60 



120 



180 

 MINUTES 



240 



300 



360 



Fig. 1. Effect of dicoumarol on growth and bacteriochlorophyll synthesis. 

 A culture was grown overnight at a light intensity of 800 fcs; one hour be- 

 fore the start of the experiment the culture was diluted and 90 ml portions 

 placed in rectangular lucite growth vessels and illuminated with 600 fcs. 

 At zero time dicoumarol (6 x 10-5 m) was added to one vessel (open points); 

 the other served as a control (filled points). Bacteriochlorophyll (^ug/ml), 

 DandB; cell mass (OD at 1000 m/i), Oand#; protein (|/g/ml),A and A. 



