Production of antimicrobial blue green pigment Pyocyanin by marine Pseudomonas aeruginosa

This study focused on isolation and molecular identification of marine bacteria which producing bioactive pigment. For that, 10 pigmented bacteria were isolated from 3 water samples collected from Mediterranean Sea, Alex., Egypt. One isolate was had efficient value to produce blue green pigment. This one was identified using molecular biology techniques and recorded in GeneBank under title of Pseudomonas aeruginosa strain OSh1 with accession number KT032066. The produced pigment was extracted, purified and characterized as pyocyanin. The pathway of pyocyanin production contains many sequential genes, the important one is phzS. This gene was detected genetically in this study using specific primers and gave PCR product with 448 bp. To confirm that, the inducible proteins for pyocyanin synthesis genes were documented using SDS-PAGE. The results represent found 2 proteins with 36 and 43 kDa for phzM and phzS, respectively. The biological activity of the produced pyocyanin at different concentrations was investigated as antimicrobial agent. The antibacterial activity was ranged between 31-42 mm of inhibition zone. Whereas, the inhibition zone for antifungal activity was ranged between 34-35 mm. The results indicate the produced pyocyanin had high activity against multi-drug resistant microbes and we can use it as marine antibiotic.