Maltose binding protein (MBP) fusion proteins with low or no affinity to amylose resins can be single-step purified using a novel anti-MBP monoclonalantibody

The maltose binding protein (MBP) fusion protein expression system is a pow erful tool to produce and isolate recombinant proteins in E, coli, Whereas the conventional isolation technique for MBP-fusion proteins takes advantag e of the binding affinity of MBP to maltose, this method is limited insofar as the biological activity of MBP has to be fully conserved for a successf ul purification. In this study, a novel monoclonal antibody (mAb) specific for MBP, termed HAM-19, was generated and its application in the purificati on and detection of MBP-fusion proteins determined. Using anti-MBP immunoaf fintiy columns, even recombinant MBP fusion products with lowered or impair ed binding affinity to maltose were purified in a single step procedure. In comparison to amylose resins, HAM-19 immunoaffinity columns showed a highe r binding capacity and affinity to MBP-fusion proteins. Furthermore, the mA b HAM-19 also provides a technical improvement over polyclonal antisera for the detection and analysis of MBP-fusion proteins which are under use in v arious forms in the fields of molecular and cellular biology.