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Periplasmic loop P2 of the MalF subunit of the maltose ATP binding cassette transporter is sufficient to bind the maltose binding protein MalE.
- Source :
-
Biochemistry [Biochemistry] 2009 Mar 17; Vol. 48 (10), pp. 2216-25. - Publication Year :
- 2009
-
Abstract
- The Escherichia coli maltose transporter belongs to the ATP binding cassette (ABC) transporter superfamily. Recently, the crystal structure of the full transporter MalFGK2 in complex with the maltose binding protein (MBP) was determined [Oldham, M. L., et al. (2007) Crystal structure of a catalytic intermediate of the maltose transporter. Nature 450, 515-522]. Using liquid-state NMR, we find that the periplasmic loop P2 of MalF (MalF-P2) folds independently in solution and adopts a well-defined tertiary structure which is similar to the one found in the crystal. MalF-P2 interacts with the maltose binding protein, independent of the transmembrane region of MalF and MalG with an affinity of 10-20 microM, in the presence and absence of substrate. Analysis of residual dipolar coupling (RDC) experiments shows that the conformation of the two individual domains of MalF-P2 is preserved in the absence of MalE and resembles the conformation in the X-ray structure. Upon titration of MalE to MalF-P2, the two domains of MalF-P2 change their relative orientation to accommodate the ligand. In particular, a conformational change of domain 2 of MalF-P2 is induced, which is distinct from the conformation found in the X-ray structure.
- Subjects :
- ATP-Binding Cassette Transporters genetics
Calorimetry
Cross-Linking Reagents chemistry
Crystallography, X-Ray
Cysteine chemistry
Databases, Protein
Escherichia coli genetics
Escherichia coli Proteins genetics
Maltose chemistry
Models, Molecular
Monosaccharide Transport Proteins genetics
Nuclear Magnetic Resonance, Biomolecular
Periplasmic Binding Proteins chemistry
Periplasmic Binding Proteins genetics
Phenanthrolines chemistry
Protein Binding physiology
Protein Conformation
Protein Structure, Secondary
Recombinant Proteins chemistry
Recombinant Proteins genetics
ATP-Binding Cassette Transporters chemistry
ATP-Binding Cassette Transporters metabolism
Escherichia coli enzymology
Escherichia coli Proteins chemistry
Escherichia coli Proteins metabolism
Monosaccharide Transport Proteins chemistry
Monosaccharide Transport Proteins metabolism
Periplasmic Binding Proteins metabolism
Protein Interaction Domains and Motifs physiology
Subjects
Details
- Language :
- English
- ISSN :
- 1520-4995
- Volume :
- 48
- Issue :
- 10
- Database :
- MEDLINE
- Journal :
- Biochemistry
- Publication Type :
- Academic Journal
- Accession number :
- 19159328
- Full Text :
- https://doi.org/10.1021/bi801376m