Maltose Binding Protein （MBP） is a part of the maltose/maltodextrin system of Eschericia coli bacteria， which is responsible for the uptake and efficient catabolism of maltodextrins. It is a complex regulatory and transport system involving many proteins and protein complexes. nMaltose binding protein MalE，MBP， is part of the maltodextrin transport system in E. coli. The maltodextrins diffuse through the LamB pore located in the outer membrane into the periplasm. The sugar is bound to MalE which prevents it to diffuse back outside. MalE passes the sugar to a complex of MalF and MalG in the cytoplasmic membrane where active tranport is mediated by the ATPase MalK. MBP molecular weight is 40，622 dalton. There are two domains in the protein with similar secondary structure （central pleated sheets are surrounded by helices） . The domains are connected by three bridges， between the domains is a deep groove in which the sugar is bound. All hydroxyl groups of the sugar are fixed by sidechains of the protein by hydrogen bonds. Some water molecules are part of the hydrogen bridge network.
应用类型
Immunofluorescence，Westren Blotting
免疫原
The malE gene is inserted in a pMAL vector （Maina et al.， 1988） and then expressed in E. coli JM109. The purified recombinant MBP protein was then used for mouse immunization.
