Pfizer Handbook of Microbial Metabolites 232 



as follows : ^ ( 1 ) Some pigment complexes are produced in 

 large quantities, up to 30 percent of the total dry weight of the 

 mycelium. (2) In many cases, the maximal pigment content 

 is reached while usable carbohydrate is still present. If har- 

 vesting is delayed, pigment disappears as autolysis sets in. 

 (3) The same pigment often is present in different genera or 

 families, suggesting solution of a metabolic problem in the 

 same way. (4) Reduction products such as anthranols, an- 

 thrones and quinhydrones sometimes are present together with 

 the parent quinone, perhaps indicating a hydrogen or electron 

 transport function. (5) Several mold pigments are antibiotic 

 toward other fungi and bacteria. 



On the other hand, it has been pointed out" that, in fungi, 

 induced mutations leading to full blocking of the production of 

 acetate-derived aromatic compounds such as anthraquinones do 

 not seem to affect the vitality of the organism. The antifunc- 

 tionalists believe that anthraquinones and perhaps some other 

 mold metabolites are merely waste or storage products due to 

 an overflow of acetate metabolism. If some of these products 

 happen to inhibit competitors, they facilitate species survival. 



A similar concept of the significance of such mold metabolites 

 has been mentioned by Dalgliesh.^ He proposed that enzyme 

 systems unable to deal with substrate because it is in large ex- 

 cess, or for some other reason, might convert it to anthraqui- 

 nones and other substances, which are eliminated, then, in a 

 kind of "detoxication" disposal mechanism. 



An enzyme chemist, F. F. Nord, has suggested- that many of 

 the metabolites produced in yields exceeding functional re- 

 quirements, or for which there is no function, accumulate be- 

 cause some of- the enzyme systems involved in the oxidative 

 sequences become saturated with respect to their substrates. 

 They are thus, in his opinion, probably products of anaerobic 



^ G. Smith, Congr. intern, botan. Paris, Rapps. et communs., 8 

 Sec. 83-89 (1954). 



^' Gosta Ehrensvard, "Developments in Aromatic Chemistry," Spe- 

 cial Publication No. 12, English Chemical Society, London, 1958, 

 p. 29. 



7 C. E. Dalgliesh, ibid., p. 14. 



^ F. F. Nord and D. D. Clarke, Arch. Biochem. and Biophys. 59 

 285 (1955). 



