23 



^c^ N/ N^ 





Sulphur- peptide spiral. 



termination. He has suggested for it the following for- 

 mula: 



N=C — S — NH3 — CHoOH 



II II 



HOCH, — NH3— S — C = N 



It is significant that the six-atom ring in this formula 

 is exactly of the type that is needed for the building of 

 peptide spirals, although no one at that time knew any- 

 thing about spiral polymerization. 



The first thing that probably happens upon mixing 

 the two ingredients is a combination of the ammonium 

 nitrogen with the formaldehyde carbon. At the same 

 time there may be oxidation of the sulphur by atmos- 

 pheric oxygen, and hydrolysis of the cyanide group, so 

 as to produce the following intermediate product: 



NH2 — CO — so — NH3 — CH.OH 



If the basic NHo — groups and the acidic — SO — 

 groups of adjacent molecules then react with each other. 



