Michael L. Oldham

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The maltose uptake system of Escherichia coli is a well-characterized member of the ATP-binding cassette transporter superfamily. Here we present the 2.8-A crystal structure of the intact maltose transporter in complex with the maltose-binding protein, maltose and ATP. This structure, stabilized by a mutation that prevents ATP hydrolysis, captures the(More)
P-glycoprotein (P-gp) is an ATP-binding cassette transporter that confers multidrug resistance in cancer cells. It also affects the absorption, distribution and clearance of cancer-unrelated drugs and xenobiotics. For these reasons, the structure and function of P-gp have been studied extensively for decades. Here we present biochemical characterization of(More)
Adenosine triphosphate (ATP)-binding cassette (ABC) transporters convert chemical energy from ATP hydrolysis to mechanical work for substrate translocation. They function by alternating between two states, exposing the substrate-binding site to either side of the membrane. A key question that remains to be addressed is how substrates initiate the transport(More)
ATP-binding cassette (ABC) transporters utilize the energy from ATP hydrolysis to transport substances across the membrane. In recent years, crystal structures of several ABC transporters have become available. These structures show that both importers and exporters oscillate between two conformations: an inward-facing conformation with the substrate(More)
ATP-binding cassette transporters couple ATP hydrolysis to substrate translocation through an alternating access mechanism, but the nature of the conformational changes in a transport cycle remains elusive. Previously we reported the structure of the maltose transporter MalFGK(2) in an outward-facing conformation in which the transmembrane (TM) helices(More)
The Rsp5 ubiquitin ligase contains a non-covalent binding site for ubiquitin within the amino-terminal lobe (N-lobe) of the HECT domain, and the X-ray crystal structure of the HECT-ubiquitin complex has been determined. Hydrophobic patch residues of ubiquitin (L8, I44, V70) were crucial for interaction with Rsp5, and amino-acid alterations at the(More)
Efficient carbon utilization is critical to the survival of microorganisms in competitive environments. To optimize energy usage, bacteria have developed an integrated control system to preferentially uptake carbohydrates that support rapid growth. The availability of a preferred carbon source, such as glucose, represses the synthesis and activities of(More)
P-glycoprotein (P-gp) is an ATP-binding cassette (ABC) transporter that confers multidrug resistance in cancer cells1,2. It also affects the absorption, distribution, and clearance of cancerunrelated drugs and xenobiotics. For these reasons, the structure and function of P-gp have been studied extensively for decades3. Here we present biochemical(More)
Cellular immunity against viral infection and tumour cells depends on antigen presentation by major histocompatibility complex class I (MHC I) molecules. Intracellular antigenic peptides are transported into the endoplasmic reticulum by the transporter associated with antigen processing (TAP) and then loaded onto the nascent MHC I molecules, which are(More)
The causative agent of severe acute respiratory syndrome (SARS) is the SARS-associated coronavirus, SARS-CoV. The nucleocapsid (N) protein plays an essential role in SARS-CoV genome packaging and virion assembly. We have previously shown that SARS-CoV N protein forms a dimer in solution through its C-terminal domain. In this study, the crystal structure of(More)