Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Cytoplasmic surface structure of bacteriorhodopsin consisting of interhelical loops and C-terminal alpha helix, modified by a variety of environmental factors as studied by C-13-NMR
Autore:
Yamaguchi, S; Yonebayashi, K; Konishi, H; Tuzi, S; Naito, A; Lanyi, JK; Needleman, R; Saito, H;
Indirizzi:
Himeji Inst Technol, Dept Life Sci, Kamigori, Hyogo 6781297, Japan Himeji Inst Technol Kamigori Hyogo Japan 6781297 ri, Hyogo 6781297, Japan Univ Calif Irvine, Dept Physiol & Biophys, Irvine, CA 92717 USA Univ CalifIrvine Irvine CA USA 92717 iol & Biophys, Irvine, CA 92717 USA Wayne State Univ, Dept Biochem, Detroit, MI USA Wayne State Univ Detroit MI USA tate Univ, Dept Biochem, Detroit, MI USA
Titolo Testata:
EUROPEAN JOURNAL OF BIOCHEMISTRY
fascicolo: 8, volume: 268, anno: 2001,
pagine: 2218 - 2228
SICI:
0014-2956(200104)268:8<2218:CSSOBC>2.0.ZU;2-6
Fonte:
ISI
Lingua:
ENG
Soggetto:
X-RAY-DIFFRACTION; PURPLE MEMBRANE; ANGSTROM RESOLUTION; LABELED BACTERIORHODOPSIN; CONFORMATIONAL-CHANGES; NEUTRON-DIFFRACTION; CRYSTAL-STRUCTURE; CATION-BINDING; N-INTERMEDIATE; PROTEIN;
Keywords:
bacteriorhodopsin; cytoplasmic surface structure; interhelical loops; C-13-NMR; C-terminal alpha helix;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
55
Recensione:
Indirizzi per estratti:
Indirizzo: Saito, H Himeji Inst Technol, Dept Life Sci, Harima Sci Garden City,Kouto 3 Chome, Kamigori, Hyogo 6781297, Japan Himeji Inst Technol Harima Sci Garden City,Kouto 3 Chome Kamigori Hyogo Japan 6781297
Citazione:
S. Yamaguchi et al., "Cytoplasmic surface structure of bacteriorhodopsin consisting of interhelical loops and C-terminal alpha helix, modified by a variety of environmental factors as studied by C-13-NMR", EUR J BIOCH, 268(8), 2001, pp. 2218-2228

Abstract

We have examined the C-13-NMR spectra of [3-C-13] Ala-labeled bacteriorhodopsin and its mutants by varying a variety of environmental or intrinsic factors such as ionic strength, temperature, pH, truncation of the C-terminala helix, and site-directed mutation at cytoplasmic loops, in order to gaininsight into a plausible surface structure arising from the C-terminal alpha helix and loops. It is found that the surface structure can be characterized as a complex stabilized by salt bridges or metal-mediated linkages among charged side chains. The surface complex in bacteriorhodopsin is most pronounced under the conditions of 10 mM NaCl at neutral pH but is destabilized to yield relaxed states when environmental factors are changed to high ionic strength, low pH and higher temperature. These two states were readilydistinguished by associated spectral changes, including suppressed (cross polarization-magic angle spinning NMR) or displaced (upfield) C-13 signals from the C-terminal alpha helix, or modified spectral features in the loop region. It is also noteworthy that such spectral changes, when going from the complexed to relaxed states, occur either when the C-terminal alpha helix is deleted or site-directed mutations were introduced at a cytoplasmic loop. These observations clearly emphasize that organization of the cytoplasmic surface complex is important in the stabilization of the three-dimensional structure at ambient temperature, and subsequently plays an essential role in biological functions.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 13/07/20 alle ore 08:00:58