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Promoter Prediction

PAntibioticPred is to predict the enzymes involved in antibiotic biosynthetic pathways in plant growth promoting Pseudomonas species.

Biosynthesis of antibiotics by plant growth promoting rhizobacteria

Plant growth promoting rhizobacteria (PGPR) play a vital role in crop protection, growth promotion and in the improvement of soil health. Some well known PGPR strains are Pseudomonas, Bacillus, Azospirillum, Rhizobium, and Serratia species. The primary mechanism of biocontrol by PGPR involves the production of antibiotics such as phenazine-1-carboxyclic acid, 2, 4-diacetyl phloroglucinol, oomycin, pyoluteorin, pyrrolnitrin, kanosamine, zwittermycin-A, and pantocin. A cascade of endogenous signals such as sensor kinases, N-acyl homoserine lactones and sigma factors regulates the synthesis of antibiotics. The genes responsible for the synthesis of antibiotics are highly conserved. The antibiotics pertain to polyketides, heterocyclic nitrogenous compounds and lipopeptides have broad-spectrum action against several plant pathogens, affecting crop plants. In addition to direct anti-pathogenic action, they also serve as determinants in triggering induced systemic resistance (ISR) in the plant system.


Phenazine is a low molecular weight secondary metabolite, nitrogen containing heterocyclic antimicrobial compound consisting of brightly coloured pigment produced by the bacterial genera pertaining to Pseudomonas, Burkholderia, Brevibacterium and Streptomyces.


Pyrrolnitrin (PRN) is a chlorinated phenylpyrrole antibiotic produced by several fluorescent and non-fluorescent pseudomonads. It was first isolated from Burkholderia pyrrocinia.


Pyoluteorin (Plt) is a phenolic polyketide with resorcinol ring. The ring is linked to a bichlorinated pyrrole moiety. Biosynthesis of pyrrole moiety is unknown. It was first isolated from P. aeruginosa followed by P. fluoresens Pf-5 and CHAO. Plt has bactericidal, herbicidal and fungicidal properties. Application of Plt to cotton seeds suppressed cotton damping-off.


Phloroglucinol antibiotics are phenolic bacterial and plant metabolites with antifungal, antibacterial, phototoxic, antiviral, and anthelmintic activity. Of particular interest is 2,4-diacetylphloroglucinol (DAPG), because of its production by fluorescent Pseudomonas spp. of worldwide origin. This polyketide antibiotic DAPG is a phenolic molecule synthesized by the condensation of three molecules of acetyl coenzymeA with one molecule of malonyl coenzymeA to produce the precursor monoacetylphloroglucinol, which is subsequently transacetylated to generate PHL utilizing a CHS-type enzyme. Biosynthetic locus of DAPG is highly conserved. It comprises the biosynthetic genes phlACBD.

Copyright 2011. CPCRI Kasaragod.