The synaptosomal-associated protein (SNAP-25) is an essential component of the core complex that mediates presynaptic vesicle trafficking. Thus, SNAP-25 is directly involved in the release of neurotransmitters and this protein exists as two alternative isoforms, SNAP25A and SNAP25B which differ by 9 amino acids in central portion of these proteins. Recombinant SNAP25B protein was expressed in E.coli and purified by using conventional chromatography techniques.