Identification of anthranilate and benzoate metabolic operons of Pseudomonas fluorescens and functional characterization of their promoter regions.
BACKGROUND
In an effort to identify alternate recombinant gene expression systems in Pseudomonas fluorescens, we identified genes encoding two native metabolic pathways that were inducible with inexpensive compounds: the anthranilate operon (antABC) and the benzoate operon (benABCD).


RESULTS
The antABC and benABCD operons were identified by homology to the Acinetobacter sp. anthranilate operon and Pseudomonas putida benzoate operon, and were confirmed to be regulated by anthranilate or benzoate, respectively. Fusions of the putative promoter regions to the E. coli lacZ gene were constructed to confirm inducible gene expression. Each operon was found to be controlled by an AraC family transcriptional activator, located immediately upstream of the first structural gene in each respective operon (antR or benR).


CONCLUSIONS
We have found the anthranilate and benzoate promoters to be useful for tightly controlling recombinant gene expression at both small (< 1 L) and large (20 L) fermentation scales.
Retallack
Diane M
DM
The Dow Chemical Company, Biotechnology Research and Development, 5501 Oberlin Dr, San Diego, CA 92121, USA. dmretallack@dow.com
Thomas
Tracey C
TC
Shao
Ying
Y
Haney
Keith L
KL
Resnick
Sol M
SM
Lee
Vincent D
VD
Squires
Charles H
CH