GLUCOSE AND OXYGEN UTILIZATION IN SYMPATHETIC GANGLIA 121 



displaying a low affinity for Bradosol. This example emphasizes the importance 

 of the pretreatment of proteins prior to an affinity experiment. 



Chairman Gerard: Thank you. I am sure that does answer some of the 

 questions that were going around, if not all of them. Dr. Fischer mentioned 

 that he had tried a number of other materials than wool. I didn't remember 

 whether he mentioned silk. 



Dr. Fischer: I did. 



Dr. Gerard: Does that not act the same? 



Dr. Fischer: One of the differences between wool and silk is that silk is a 

 crystalline protein, whereas wool is a fibrous protein. Intact, degummed silk 

 stains a deep violet when stained with crystal violet, whereas intact wool does 

 not take the stain, i.e. it is gram-negative. 



Chairman Gerard: Have you by any chance had a chance to study the 

 wools from sheep that have been raised on a copper deficient diet or manganese 

 diet in which you get changes in the wiggliness and in the color and so on, or 

 abnormal protein molecules? 



Dr. Fischer: No. 



Chairman Gerard: It might be a possible lead for you. 



Dr. Morales: With respect to the other proteins I think the main difference 

 between silk and keratin would be the number of polar groups and silk is noto- 

 riously low, so I think if you wanted to try a different protein you ought to 

 try one that is not in the same series. 



The reason I had asked you about the type of binding is that, if my arithme- 

 tic is correct, you have something like one molecule bound per ten. That means 

 that you must have pulled an awful lot of this stuff into it. 



Now, if you say this is due to hydrogen bond or due to some electrostatic 

 attraction, you class this as a rather loose binding and this seems a little con- 

 tradictory to me. 



Dr. Fischer: You have 0.2 gm. of substance dissolved in 50 cc. of distilled 

 water and one gm. of wool; this means that 20% of substance was taken, 

 calculated on the basis of the weight of the wool. The substance therefore is 

 present as a surplus. After 10 minutes at 90°C and pH 5.2 equilibrium has been 

 reached and the affinity experiment is completed by rinsing the wool three 

 times with distilled water at room temperature. Then we believe that the sub- 

 stance is bound to the wool mainly by hydrogen bonds. 



Dr. Morales: How do you know this? 



Dr. Fischer: I do not know, I only assume, but I am in good company with 

 my assumption as H. R. Chipalkatti, C. H. Giles, and D. G. M. Vallance 

 (Journal Soc. Dyers a. Color. 70: (1954), 4375) believe the same after deter- 

 mining the adsorption of organic compounds by wool, silk and nylon from 

 aqueous and non-aqueous solutions. 



