Cloning and Expression of Genes Encoding Enzymes Involved in the Synthesis of Phenolic Antibiotic in Recombinant E. Coli

ABSTRACT

Methicillin-resistant Staphylococcus aureus (MRSA) causes serious public health problems throughout the world. In order to find an appropriate antibiotic against S. aureus scientists have focused on 2,4-diacetylphloroglucinol (DAPG) antibiotic produced by certain Pseudomonas spp. strains. Pseudomonas sp. strains residing in the rhizosphere have been considered due to their ability to produce antimicrobial metabolites which protect plants against different types of pathogens. In this study, Pseudomonas fluorescens UTPf100 was selected among 103 different Iranian isolates as an overproducer of DAPG on the basis of biological control and DAPG production. From this strain we isolated four genes that directly affect DAPG biosynthesis. The isolation was then confirmed by nested PCR and digestion. The encoding sequences responsible for DAPG biosynthesis were sub-cloned to pET28a (+) as an expression vector and transformed in E. coli BL21. To the best of our knowledge this is the first report for expression of the operon responsible for DAPG synthesys in recombinant E. coli.

Keywords:

• biological control
• phenolic antibiotic
• Pseudomonas
• expression