II !l II li 



394 BACTERIOLOGICAL CHEMISTRY 



201° C, from P. sjnnulosum and A. fmnigatus have 

 already been described as antibiotics (see pp. 163, 179). 

 Phoenicin, 2 : 2'-dihydroxy-4 : 4'-di-methyldiqiiinone, 



yellow brown crystals, m.p. 



230° C, produced by P. phceniceiim and P. ruhrum is a 

 condensed toluquinone pigment. Under appropriate 

 conditions of growth, fumigatin and phoenicin occur in 

 the colourless reduced quinol form, in the culture media. 

 As suggested on page 393 the quinones and quinols form 

 an oxidation-reduction system and may serve as a 

 hydrogen transfer mechanism in respiration. Flavo- 

 glaucin, C19H28O3, lemon yellow needles, m.p. 105° C. and 

 auroglaucin, C19H22O3, orange crystals, m.p. 152° C, 

 which occur in the mycelium of A. glaucus furnish 

 examples of quinol pigments. Flavoglaucin has one of 

 the structures : — 



OH 



corresponding unsaturated analogue in ^vhich the side 

 chain — 00.(CHo)6()H3 is replaced l)y — (J0(CH=CH)3 

 CH3. 



