Purification and characterization of gamma poly glutamic acid from newly Bacillus licheniformis NRC20

Abstract

γ-poly glutamic acid (γ-PGA) has received considerable attention for pharmaceutical and biomedical applications. γ-PGA from the newly isolate Bacillus licheniformis NRC20 was purified and characterized using diffusion distance agar plate, mass spectrometry and thin layer chromatography. All analysis indicated that γ-PGA is a homopolymer composed of glutamic acid. Its molecular weight was determined to be 1266. kDa. It was composed of l- and d-glutamic acid residues. An amplicon of 3050 represents the γ-PGA-coding genes was obtained, sequenced and submitted in genbank database. Its amino acid sequence showed high similarity with that obtained from B. licheniformis strains. The bacterium NRC 20 was independent of l-glutamic acid but the polymer production enhanced when cultivated in medium containing l-glutamic acid as the sole nitrogen source. Finally we can conclude that γ-PGA production from B. licheniformis NRC20 has many promised applications in medicine, industry and nanotechnology.