Managing gene expression in Pseudomonas simiae EGD-AQ6 for chloroaromatic compound degradation.

Pseudomonas simiae EGD-AQ6 is capable of utilizing chloroaromatic compound i.e., 2-4-D efficiently in its biofilm phenotype. The differential accumulation of intermediate 4-chlorocatechol rates were significant in planktonic and biofilm phenotypes, as well as in the  increased biofilm adapted cell numbers. Interestingly, response surface analysis demonstrated the combined positive effects of 2-4-D degradation and 4-CCA accumulation rates and the gene expression profiles, with significant up-regulation of degradative and biofilm genes, and greater participation of pellicle genes in the biofilm phenotypes than their planktonic counterparts, thereby revealing a phenotype variation. It positively validated the physiological data. Furthermore, the sequence similarity of the 2-4-D catabolic and biofilm-forming proteins (pel ABCDEFG and pga ABCD), which are responsible for building carbohydrate rich extracellular matrix, were significant with the respective organisms. This is the first study, which endorses this strain to be unique in efficient chloro-aromatic degradation through phenotype variation, thereby proving a potential candidate in the improvement of bioremediation technologies.