Abstract
Bone morphogenetic protein-2 (BMP-2) is one of the most interesting of the approx. 14 BMPs which belong to the transforming-growth-factor-β (TGF-β) superfamily. BMP-2 induces bone formation and thus plays an important role as a pharmaceutical protein.
BMP-2 has been produced in form of inactive inclusion bodies in E. coli [1] and after solubilization and renaturation, the biologically active dimeric form of BMP-2 is generated [2]. However, inactive monomers of BMP-2 are also formed during the renaturation process which need to be separated from the active dimeric BMP-2.
Goal of the project is the development of a continuous gradient SMB-process [3] exploiting two different salt concentrations in the feed solution and in the desorbent. A three-zone-configuration is designed based on a systematic study of the adsorption equilibrium of the monomers and dimers of BMP-2 at different salt concentrations. These equilibrium data allow to specify suitable salt concentrations and flow rates of the SMB-process offering the potential to collect the better adsorbed dimer with high purity at the extract port of the unit.
In this presentation are presented:
1) A theoretical study of the three-zone-gradient-SMB process
2) The current state of the experimental work
[1] Vallejo, L.F., Brokelmann, M., Marten, S., Trappe, S., Cabrera-Crespo, J., Hoffmann, A., Gross, G., Weich, H.A. and Rinas, U. (2002) Renaturation and purification of bone morphogenetic protein-2 produced as inclusion bodies in high-cell-density cultures of recombinant Escherichia coli. J. Biotechnol., 94, 185-194
[2] Vallejo, L.F. and Rinas, U. (2004) Optimized procedure for renaturation of recombinant human bone morphogenetic protein-2 at high protein concentration. Biotechnol. Bioeng., 85, 601-609
[3] Antos, D., Seidel-Morgenstern, A. (2001) Application of gradients in the simulated moving bed processes. Chem. Eng. Sci. 56, 6667-6682
