LIPIDS 



163 



300 



2 200 



c 

 a> 



00 

 >> 

 X 



O 



100 



60 120 



Time, minutes 



180 



Figure 6. The oxidation of hydrocarbons by Proactinomyces opacus. Redrawn 

 from Webley and DeKock (543), by permission of the Cambridge University Press. 



ZoBell (577) reviews our knowledge of the process in bacteria. Inter- 

 mediates appearing during the oxidation of naphthalene by Nocardia 

 sp. suggest that benzenoid compounds may be formed (520). 



Hydrocarbons produced by fungi fall into two groups: ethylene and 

 its derivatives, and the substituted hydrocarbon polyenes and poly- 

 enynes. 



From the biological effects of volatile products of Penicillium 

 digitatum it seemed probable that the organism produces ethylene 

 (59, 378). This has been confirmed (571); ethylene is probably pro- 

 duced also by Blastomyces dermatitidis (394) and by Fusariurn oxy- 

 sporum v. lycopersict (167). However, the ethylene produced by 

 fungus-infected plant tissues is believed to be a host product, stim- 

 ulated quantitatively by infection, rather than a fungus metabolite 

 (559). 



An interesting volatile hydrocarbon, 2-methylbutene-2 (trimethyl- 

 ethylene), is formed by uredospores of Puccinia graminis tritici and 

 is perhaps responsible for self-inhibition of germination of the rust 

 spores (199). 



Several antibiotics produced by fungi and actinomycetes are in two 



