Cloning, Expression and Characterization of the Anticancer Protein Azurin from an Indigenous Strain Pseudomonas aeruginosa SSj

Azurin is a novel anticancer protein, mainly produced from Pseudomonas aeruginosa and few other Gram-negative bacteria. In this study, azurin gene (azu) from a native Pseudomonas aeruginosa strain SSj was amplified using PCR with specific primers. The azurin gene (418 bp) was sequenced and submitted in Genbank. The PCR amplicon was digested with BamHI and HindIII and inserted into expression vector pET-22b(+). The recombinant protein was expressed in Escherichia coli BL21 (DE3) after induction with IPTG. Protein purification was done using Ni NTA agarose. The SDS-PAGE analysis of purified samples with Coomassie brilliant blue showed a band with an apparent molecular weight of about 14 kDa. Structural characterization of purified protein was done by FTIR, MALDI-TOF and LC–MS/MS analysis.