Serrapeptidase is pharmaceutically, entomologically important protease isolated from Serratia marcescens, a saprophytic organism. Presently available pharmaceutical product, used as an anti-inflammatory drug, has been isolated from Serratia piscatorum, an entrobacterium found in intestinal canal of silk worm. Here we report the characterization of the gene isolated from an organism of plant source with an objective to understand the biochemical basis of its encoded protein. The genomic DNA of Serratia marcescens MTCC 8708 was isolated using standard protocol and used as a source for the gene. Primers corresponding to Serrapeptidase were designed based on the sequences available in the data base and gene amplified. A single amplified DNA of 1.5Kb was purified and cloned into pJET 1.2 cloning vector and subjected for sequencing. The sequence analysis revealed the presence of single Open reading frame (ORF) of 1464 nucleotide with high G+C content (58%) encoding a protein of 487 amino acid residues. The sequence alignment using the BLAST search in NCBI Gen Bank showed 100% homology with serralysin metalloprotease from Serratia marcescens strain 2170. The derivedamino acid sequence was further analyzed for conserved domains and motifs in database which showed the presence of three conserved domains for Zinc binding site and Histidine amino acid at active site. The similarities of these regions with other proteases like thermolysin, and a neutral protease of Bacillus subtilis, suggest that the derived amino acid sequence from the gene may correspond to a metalloprotease. The gene may be used to produce a protein for pesticidal / pharmaceutical application
