Genetic evidence of a high-affinity cyanuric acid transport system in Pseudomonas sp. ADP.
The Pseudomonas sp. ADP plasmid pADP-1 encodes the activities involved in the hydrolytic degradation of the s-triazine herbicide atrazine. Here, we explore the presence of a specific transport system for the central intermediate of the atrazine utilization pathway, cyanuric acid, in Pseudomonas sp. ADP. Growth in fed-batch cultures containing limiting cyanuric acid concentrations is consistent with high-affinity transport of this substrate. Acquisition of the ability to grow at low cyanuric acid concentrations upon conjugal transfer of pADP1 to the nondegrading host Pseudomonas putida KT2442 suggests that all activities required for this phenotype are encoded in this plasmid. Co-expression of the pADP1-borne atzDEF and atzTUVW genes, encoding the cyanuric acid utilization pathway and the subunits of an ABC-type solute transport system, in P. putida KT2442 was sufficient to promote growth at cyanuric acid concentrations as low as 50 μM in batch culture. Taken together, our results strongly suggest that the atzTUVW gene products are involved in high-affinity transport of cyanuric acid.
Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide/Consejo Superior de Investigaciones Científicas/Junta de Andalucía, Sevilla, Spain; Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Sevilla, Spain.
Ana I
AI
Platero
Eduardo
E
Santero
Fernando
F
Govantes
D003470:Culture Media / Q000737:chemistry; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism*; D010957:Plasmids; D011549:Pseudomonas / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D014227:Triazines / Q000378:metabolism*
D003470:Culture Media; D026901:Membrane Transport Proteins; D014227:Triazines; C004632:cyanuric acid
Pseudomonas; atrazine biodegradation; cyanuric acid; membrane solute transport