Degradation of B-Mcthylhexanc by a Pseudomonas 



479 



FLAME IONIZATION 



t 



2-METHYLHEXANOIC 



TIME 



CHROMATOGRAM OF FATTY ACIDS FROM 

 2 -METHYLHEXANE INCUBATION WITH 

 2-METHYLHEXANE-GROWN PSEUDOMONAS CELLS 



6' 03 1091 _ __ ^ 



FIGURE 2 



ments quoted above - tliat wo-valeric acid is hardly oxidized by 

 heptane-adapted cells. 



Figure 2 shows a chromatogram of fatty-acid methyl esters 

 obtained from 2-methylhexane incubation with 2-methylhexane- 

 adapted cells. 



It is seen that here no i^o- valeric acid has accumulated, 

 presumably because of its high oxidation rate. 



However, both methyl-substituted hexanoic acids were found 

 to be present. The presence of the 2-methyl derivative proves 

 that both the 2-methylhexane-adapted cells and the heptane- 

 adapted ones can oxidize Ci. Decrease of the ratio of the 5- 

 methyl- to the 2-methyl isomer as compared with Figure 1 fur- 

 ther demonstrates the increased oxidation of 5-methylhexanoic 

 acid by cells adapted to 2-methylhexane. This also is quite in line 

 with the multiple adaptation experiments. 



Summarizing, we may conclude from the analytical experi- 



