Optimization and efficient purification of recombinant Omp28 protein of Brucella melitensis using Triton X-100 and β-mercaptoethanol

► Expression of recombinant Omp28 protein of Brucella melitensis in pET28a and pQE30UA vectors. ► Use of 1% Triton X-100 and 20 mM β-mercaptoethanol in buffers for single step purification. ► The modified purification protocol yielded 3.6-fold higher rOmp28 protein. ► The modified procedure may be useful for purification of proteins from inclusion bodies.