Cloning and characterization of phloroglucinol biosynthetic gene phlC from an Indian strain of Pseudomonas fluorescens

Abstract

Phloroglucinol or 2,4-diacetyl phloroglucinol (DAPG) is a polyketide compound produced by gram negative soil bacteria Pseudomonas. It shows broad spectrum antibacterial and antifungal properties against soil-borne plant pathogens. In Pseudomonas spp., genes for biosynthesis of 2,4-DAPG are localized in phlABCD operon. All the four genes in phlABCD operon are indispensable and DAPG synthesis is attenuated even in the absence of one of the genes. In the present study, we identified and cloned phlC gene from an Indian strain of Pseudomonas and analyzed its sequence. The structural details of the PHLC protein was generated by three-dimensional homology modelling. Additionally, stereo-chemical properties of PHLC were analyzed by Ramachandran plot analysis and the generated model was validated by PDBsum. Our results demonstrate that the cloned PHLC protein contains structural features typical of a condensing enzyme involved in polyketide synthesis.