Crystal structure of the bacterial protein export chaperone secB.
SecB is a bacterial molecular chaperone involved in mediating translocation of newly synthesized polypeptides across the cytoplasmic membrane of bacteria. The crystal structure of SecB from Haemophilus influenzae shows that the molecule is a tetramer organized as a dimer of dimers. Two long channels run along the side of the molecule. These are bounded by flexible loops and lined with conserved hydrophobic amino acids, which define a suitable environment for binding non-native polypeptides. The structure also reveals an acidic region on the top surface of the molecule, several residues of which have been implicated in binding to SecA, its downstream target.
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Department of Biological Chemistry, The University of Michigan Medical School, 1301 E. Catherine Road, Ann Arbor, Michigan 48109, USA. zhaohui@umich.edu
Knafels
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Yoshino
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D000251:Adenosine Triphosphatases / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D001665:Binding Sites; D002352:Carrier Proteins / Q000378:metabolism; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D019281:Dimerization; D029968:Escherichia coli Proteins; D006193:Haemophilus influenzae / Q000737:chemistry*; D026901:Membrane Transport Proteins; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry* / Q000378:metabolism*; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D018583:Pliability; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D000069816:SEC Translocation Channels; D000081416:SecA Proteins; D016415:Sequence Alignment
D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D018832:Molecular Chaperones; D010455:Peptides; D000069816:SEC Translocation Channels; C057842:SecB protein, Bacteria; D000251:Adenosine Triphosphatases; D000081416:SecA Proteins