86 



F. §ORM 



Table 7 



PEPTIDES OF ARGININE AND HISTIDINE ISOLATED 

 FROM PARTIAL ACID HYDROLYSATES OF BOVINE 

 CHYMOTRYPSINOGEN AND TRYPSINOGEN 



[5 



* This sequence has been confirmed very recently by enzymic hydrolysis. 



Table 8 shows that there is also a marked resemblance in the composition 

 and structure of the lysine-containing peptides of the two proteins, although 

 in this case, owing to the large number of lysine residues present and the 

 small number of peptides isolated, no definite conclusions as to their struc- 

 tural similarities can be drawn. 



A general review of our preliminary results on the comparison of the 

 microstructure of chymotrypsinogen and trypsinogen first of all shows that 

 our findings are in full agreement with the structural fragments so far de- 

 tected in these proteins by other workers. The extensive structural similarity 

 estabhshed for a number of peptides at defined sites in the molecules of the 

 two proteins permits the conclusion that there is considerable resemblance 

 in their microstructures. However, the molecules must necessarily also con- 

 tain larger peptide fragments which diff"er in the two cases; this follows 



