4-Chlorobenzoate uptake in Comamonas sp. strain DJ-12 is mediated by a tripartite ATP-independent periplasmic transporter.
The fcb gene cluster involved in the hydrolytic dehalogenation of 4-chlorobenzoate is organized in the order fcbB-fcbA-fcbT1-fcbT2-fcbT3-fcbC in Comamonas sp. strain DJ-12. The genes are operonic and inducible with 4-chloro-, 4-iodo-, and 4-bromobenzoate. The fcbT1, fcbT2, and fcbT3 genes encode a transporter in the secondary TRAP (tripartite ATP-independent periplasmic) family. An fcbT1T2T3 knockout mutant shows a much slower growth rate on 4-chlorobenzoate compared to the wild type. 4-Chlorobenzoate is transported into the wild-type strain five times faster than into the fcbT1T2T3 knockout mutant. Transport of 4-chlorobenzoate shows significant inhibition by 4-bromo-, 4-iodo-, and 4-fluorobenzoate and mild inhibition by 3-chlorobenzoate, 2-chlorobenzoate, 4-hydroxybenzoate, 3-hydroxybenzoate, and benzoate. Uptake of 4-chlorobenzoate is significantly inhibited by ionophores which collapse the proton motive force.
Chae
Jong-Chan
JC
Biotech Center for Agriculture and the Environment, Rutgers University, New Brunswick, NJ 08901-8520, USA.
Zylstra
Gerben J
GJ
D000255:Adenosine Triphosphate / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D002723:Chlorobenzoates / Q000378:metabolism*; D020585:Comamonas / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D005810:Multigene Family; D033903:Periplasmic Proteins / Q000235:genetics / Q000378:metabolism*; D011995:Recombination, Genetic
D001426:Bacterial Proteins; D002723:Chlorobenzoates; D026901:Membrane Transport Proteins; D033903:Periplasmic Proteins; D000255:Adenosine Triphosphate; C040768:4-chlorobenzoic acid