Aspartic Acid 



Dibasic acid, 

 reaction acid 



Branched Polypeptid. 

 GlvsvI-alanyl-diaspartic-Acfd 



This^tetrep-ptidcan develop :;r.>:3ges aior.g 

 two branches, beside the main chain, ks 

 reaction is acid due to the prer order ence 

 ofcarfcoxyl groups. Such poly r=ptids 

 linked would give an acid protein.' 



Serin 



Proiin 



Valia 



Arginin 



Diamino acid,- 

 reaction basic 



Schematic representation of a protein molecule 

 PLATE If. SC'IIKMATIC KKPKKSKXTATIOX OF A PROTEIN MOLECULE. 



This is the supposed composition of the protainin of tlu salmon (sahninei. Six 

 jx'ptids. f.-u-h ooinpu^cd uf t\\<> niokvules of the diumino acid arginin and one 

 aeid. are linked to^rtlic-r. The protein is strongly bask- because f the 



v of the uininu jrnuips. 



