178 BACTERIOLOGICAL CHEIMISTRY 



CH N CH 



^'\ /\ ^-\ 

 ^ \/ \^ \ , 

 CH C C CH 



I II I II 



CH C C CH 



% /\ ^\ / 

 %/ \^ \/ 

 CH N CO 



II 

 CO N CH 



/\ ,^\ /%, 

 / \^ \/ % 

 CH C C CH 



li I II I 



CH C C CH 



\^ \/ \/ 

 CH N CH 



CH3 



which breaks down to 



o- 



CH N CO CH N C 



^\ /% /\ ^^\ /%^ /% 



^ \/ %/ \ ^ \/ %/ % 



CH C C CH CH C C CH 



I II I II .=^ 1 II I I 



CH C C CH CH C C CH 



% /\ /% / % /\ ^\ ^ 



%/ \/ %/ %/ \^ \^ 



CH N CH CH N+ CH 



I I 



CH3 CH3 



with a structure not unlike that of iodinin (see p. 168) 

 which is also a phenazine derivative. It is formed in the 

 first two or three days of growth of the organism ; 

 pyocyanase occurs in cultures two to three months old. 

 Cultures of intermediate age contain a second pigment, 

 yellow in colour, which is a degradation product of 

 pyocyanin, known as hemipyocyanin, and having the 

 structure , a -hydro xy-phenazine , 



