The Uptake of Aliphatic Amides by Pseudomonas Aeruginosa

SUMMARY: The uptake of aliphatic amides by Pseudomonas aeruginosa 8602 was studied by using 1-14C-acetamide and 1-14C-N-acetylacetamide (a non-metabolizable analogue). 1-14C-acetamide was accumulated by the wild-type strains and by an amidase-negative mutant. The maximum ratio of internal to external concentration measured was 100:1. 1-14C-N-acetylacetamide was concentrated by the wild-type strain and the maximum ratio of internal to external concentration measured was 80:1. No difference was detected in amide uptake as between induced and non-induced cultures of the wild-type or mutant strains. It is concluded that the organism possesses a constitutative permease for these amides. Cyano-acetamide had no significant effect on N-acetylacetamide accumulation by the wild-type strain at concentrations which repressed amidase synthesis. Repression of amidase synthesis by amide analogue repressors is therefore not due to inhibition of amide uptake by the bacteria.