Location of helix III in the lactose permease of Escherichia coli as determined by site-directed thiol cross-linking

被引:14
作者
Wang, QD
Kaback, HR [1 ]
机构
[1] Univ Calif Los Angeles, Howard Hughes Med Inst, Dept Physiol, Los Angeles, CA 90095 USA
[2] Univ Calif Los Angeles, Inst Mol Biol, Dept Microbiol & Mol Genet, Los Angeles, CA 90095 USA
关键词
D O I
10.1021/bi991853a
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The six N-terminal transmembrane helices (N-6) and the six C-terminal transmembrane helices (C-6) in the lactose permease of Escherichia coli, each containing a single Cys residue, were coexpressed, and cross-linking was studied. The proximity of paired Cys residues in helices III (position 78, 81, 84, 86, 87, 88, 90, 93, or 96) and VII (position 227, 228, 231, 232, 235, 238, 239, 241, 243, 245, or 246) was examined by using iodine or two rigid homobifunctional thiol-specific cross-linking reagents with different lengths [N,N'-o-phenylenedimaleimide (o-PDM; 6 Angstrom) and N,N'-p-phenylenedimaleimide (p-PDM; 10 Angstrom)]. Cys residues in the periplasmic half of helix III (position 87, 93, or 96) cross-link to Cys residues in the periplasmic half of helix Vn (position 235, 238, 239, 241, or 245). In contrast, no cross-linking is evident with paired Cys residues near the cytoplasmic ends of helices III (position 78 or 81) and VII (position 227, 228, 213, 232, or 235). Therefore, the periplasmic halves of helices III and VII are in close proximity, and the helices tilt away from each other toward the cytoplasmic face of the membrane. On the basis of the findings, a modified helix packing model for the permease is presented.
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页码:16777 / 16782
页数:6
相关论文
共 43 条
  • [1] INVIVO EXPRESSION OF THE LACY GENE IN 2 SEGMENTS LEADS TO FUNCTIONAL LAC PERMEASE
    BIBI, E
    KABACK, HR
    [J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1990, 87 (11) : 4325 - 4329
  • [2] INTRAMOLECULAR DISLOCATION OF THE COOH TERMINUS OF THE LAC CARRIER PROTEIN IN RECONSTITUTED PROTEOLIPOSOMES
    CARRASCO, N
    HERZLINGER, D
    MITCHELL, R
    DECHIARA, S
    DANHO, W
    GABRIEL, TF
    KABACK, HR
    [J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES, 1984, 81 (15): : 4672 - 4676
  • [3] Molecular mechanism of transmembrane signaling by the aspartate receptor: A model
    Chervitz, SA
    Falke, JJ
    [J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1996, 93 (06) : 2545 - 2550
  • [4] PROPERTIES AND PURIFICATION OF AN ACTIVE BIOTINYLATED LACTOSE PERMEASE FROM ESCHERICHIA-COLI
    CONSLER, TG
    PERSSON, BL
    JUNG, H
    ZEN, KH
    JUNG, K
    PRIVE, GG
    VERNER, GE
    KABACK, HR
    [J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1993, 90 (15) : 6934 - 6938
  • [5] ROLE OF PROLINE RESIDUES IN THE STRUCTURE AND FUNCTION OF A MEMBRANE-TRANSPORT PROTEIN
    CONSLER, TG
    TSOLAS, O
    KABACK, HR
    [J]. BIOCHEMISTRY, 1991, 30 (05) : 1291 - 1298
  • [6] ROLE OF THE CHARGE PAIR ASPARTIC ACID-237-LYSINE-358 IN THE LACTOSE PERMEASE OF ESCHERICHIA-COLI
    DUNTEN, RL
    SAHINTOTH, M
    KABACK, HR
    [J]. BIOCHEMISTRY, 1993, 32 (12) : 3139 - 3145
  • [7] Chemical rescue of Asp237->Ala and Lys358->Ala mutants in the lactose permease of Escherichia coli
    Frillingos, S
    Kaback, HR
    [J]. BIOCHEMISTRY, 1996, 35 (41) : 13363 - 13367
  • [8] CYSTEINE-SCANNING MUTAGENESIS OF PUTATIVE HELIX-VII IN THE LACTOSE PERMEASE OF ESCHERICHIA-COLI
    FRILLINGOS, S
    SAHINTOTH, M
    PERSSON, B
    KABACK, HR
    [J]. BIOCHEMISTRY, 1994, 33 (26) : 8074 - 8081
  • [9] Cys-scanning mutagenesis:: a novel approach to structure-function relationships in polytopic membrane proteins
    Frillingos, S
    Sahin-Tóth, M
    Wu, JH
    Kaback, HR
    [J]. FASEB JOURNAL, 1998, 12 (13) : 1281 - 1299
  • [10] HATTORI M, 1986, ANAL BIOCHEM, V152, P1291