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Transmembrane orientation and topology of the NADH:quinone oxidoreductase putative quinone binding subunit NuoH

Roth, Robert LU and Hägerhäll, Cecilia LU (2001) In Biochimica et Biophysica Acta - Bioenergetics 1504(2-3). p.352-362
Abstract
NADH:quinone oxidoreductase, or Complex I, is a multi-subunit membrane-bound enzyme in the respiratory chain of many pro- and eukaryotes. The enzyme catalyzes the oxidation of NADH and donates electrons to the quinone pool, coupled to proton translocation across the membrane, but the mechanism of energy transduction is not understood. In bacteria the enzyme consists of 14 subunits, seven membrane spanning and seven protruding from the membrane. The hydrophobic NuoH (NQO8, ND1, NAD1, NdhA) subunit is seemingly involved in quinone binding. A homologous, structurally and most likely functionally similar subunit is also found in F420H2 oxidoreductases and in complex membrane-bound hydrogenases. We have made theoretical analyses of NuoH and... (More)
NADH:quinone oxidoreductase, or Complex I, is a multi-subunit membrane-bound enzyme in the respiratory chain of many pro- and eukaryotes. The enzyme catalyzes the oxidation of NADH and donates electrons to the quinone pool, coupled to proton translocation across the membrane, but the mechanism of energy transduction is not understood. In bacteria the enzyme consists of 14 subunits, seven membrane spanning and seven protruding from the membrane. The hydrophobic NuoH (NQO8, ND1, NAD1, NdhA) subunit is seemingly involved in quinone binding. A homologous, structurally and most likely functionally similar subunit is also found in F420H2 oxidoreductases and in complex membrane-bound hydrogenases. We have made theoretical analyses of NuoH and NuoH-like polypeptides and experimentally analyzed the transmembrane topology of the NuoH subunit from Rhodobacter capsulatus by constructing and analyzing alkaline phosphatase fusion proteins. This demonstrated that the NuoH polypeptide has eight transmembrane segments, and four highly conserved hydrophilic sequence motifs facing the inside, bacterial cytoplasm. The N-terminal and C-terminal ends are located on the outside of the membrane. A topology model of NuoH based on these results is presented, and implications from the model are discussed. (Less)
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author
organization
publishing date
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Contribution to journal
publication status
published
subject
keywords
Complex I, NADH:quinone oxidoreductase, Hydrogenase, F420, NuoH, ND1, NQO8, NAD1, NdhA, Alkaline phosphatase fusion, (Rhodobacter capsulatus)
in
Biochimica et Biophysica Acta - Bioenergetics
volume
1504
issue
2-3
pages
352 - 362
publisher
Elsevier
external identifiers
  • scopus:0035795161
ISSN
0005-2728
DOI
10.1016/S0005-2728(00)00265-6
language
English
LU publication?
yes
id
973df07c-30ef-4fe1-84ad-80a0f6f8be8c (old id 125050)
date added to LUP
2007-07-06 14:31:48
date last changed
2018-05-29 09:46:21
@article{973df07c-30ef-4fe1-84ad-80a0f6f8be8c,
  abstract     = {NADH:quinone oxidoreductase, or Complex I, is a multi-subunit membrane-bound enzyme in the respiratory chain of many pro- and eukaryotes. The enzyme catalyzes the oxidation of NADH and donates electrons to the quinone pool, coupled to proton translocation across the membrane, but the mechanism of energy transduction is not understood. In bacteria the enzyme consists of 14 subunits, seven membrane spanning and seven protruding from the membrane. The hydrophobic NuoH (NQO8, ND1, NAD1, NdhA) subunit is seemingly involved in quinone binding. A homologous, structurally and most likely functionally similar subunit is also found in F420H2 oxidoreductases and in complex membrane-bound hydrogenases. We have made theoretical analyses of NuoH and NuoH-like polypeptides and experimentally analyzed the transmembrane topology of the NuoH subunit from Rhodobacter capsulatus by constructing and analyzing alkaline phosphatase fusion proteins. This demonstrated that the NuoH polypeptide has eight transmembrane segments, and four highly conserved hydrophilic sequence motifs facing the inside, bacterial cytoplasm. The N-terminal and C-terminal ends are located on the outside of the membrane. A topology model of NuoH based on these results is presented, and implications from the model are discussed.},
  author       = {Roth, Robert and Hägerhäll, Cecilia},
  issn         = {0005-2728},
  keyword      = {Complex I,NADH:quinone oxidoreductase,Hydrogenase,F420,NuoH,ND1,NQO8,NAD1,NdhA,Alkaline phosphatase fusion,(Rhodobacter capsulatus)},
  language     = {eng},
  number       = {2-3},
  pages        = {352--362},
  publisher    = {Elsevier},
  series       = {Biochimica et Biophysica Acta - Bioenergetics},
  title        = {Transmembrane orientation and topology of the NADH:quinone oxidoreductase putative quinone binding subunit NuoH},
  url          = {http://dx.doi.org/10.1016/S0005-2728(00)00265-6},
  volume       = {1504},
  year         = {2001},
}