1C2 M. D. KAMEN 



Discussion 



Amon : Did you get (cytochrome c from the whole cells or trom particles isoluteti 

 from the cell? 



Kamen : Fii-st, from the whole cell by sonic treatment. In this treatment, the 

 supernatant becomes pink and you get most of your cytochrome that way. 

 There is, however, always a certain amount of cytochrome left in the particles, 

 which requires further treatment to get it out, and there is always some that does 

 not come out at all. 



Amon: My question implied: what is the evidence for the statement that, in 

 these bacteria, most of the cytochrome is in the particles? 



Kamen : I did not say that most of it is in the particles. I said that in this bac- 

 terium most of it is easily extractable. 



Amon : Is that true of all photosynthetic bacteria or just of certain kinds? 



Kamen : Only for these two we know about. 



Lucile Smith: If you prepare the particles carefully, you can find all the 

 cytochromes in them. It is only when you prepare them with the sonic vibrator 

 that you get the C3^tochromes in solution. 



Kamen : There is an enormous amount of cytochromes in these organisms by 

 comparison with normal aerobic tissue. The amount is considerable even by com- 

 parison with live mitochondria. 



[See also Discussion following paper by Albert R. Krall, pp. 320-325.] 



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