---
_id: '1209'
abstract:
- lang: eng
  text: 'NADH-ubiquinone oxidoreductase (complex I) is the largest (∼1 MDa) and the
    least characterized complex of the mitochondrial electron transport chain. Because
    of the ease of sample availability, previous work has focused almost exclusively
    on bovine complex I. However, only medium resolution structural analyses of this
    complex have been reported. Working with other mammalian complex I homologues
    is a potential approach for overcoming these limitations. Due to the inherent
    difficulty of expressing large membrane protein complexes, screening of complex
    I homologues is limited to large mammals reared for human consumption. The high
    sequence identity among these available sources may preclude the benefits of screening.
    Here, we report the characterization of complex I purified from Ovis aries (ovine)
    heart mitochondria. All 44 unique subunits of the intact complex were identified
    by mass spectrometry. We identified differences in the subunit composition of
    subcomplexes of ovine complex I as compared with bovine, suggesting differential
    stability of inter-subunit interactions within the complex. Furthermore, the 42-kDa
    subunit, which is easily lost from the bovine enzyme, remains tightly bound to
    ovine complex I. Additionally, we developed a novel purification protocol for
    highly active and stable mitochondrial complex I using the branched-chain detergent
    lauryl maltose neopentyl glycol. Our data demonstrate that, although closely related,
    significant differences exist between the biochemical properties of complex I
    prepared from ovine and bovine mitochondria and that ovine complex I represents
    a suitable alternative target for further structural studies. '
acknowledgement: "J.A.S supported in part by a Medical Research D.G.Council UK Ph.D.
  fellowship.\r\nThis work was supported in part by European Union's 2020 Research
  and Innovation Program under Grant 701309. \r\n"
author:
- first_name: James A
  full_name: Letts, James A
  id: 322DA418-F248-11E8-B48F-1D18A9856A87
  last_name: Letts
  orcid: 0000-0002-9864-3586
- first_name: Gianluca
  full_name: Degliesposti, Gianluca
  last_name: Degliesposti
- first_name: Karol
  full_name: Fiedorczuk, Karol
  id: 5BFF67CE-02D1-11E9-B11A-A5A4D7DFFFD0
  last_name: Fiedorczuk
- first_name: Mark
  full_name: Skehel, Mark
  last_name: Skehel
- first_name: Leonid A
  full_name: Sazanov, Leonid A
  id: 338D39FE-F248-11E8-B48F-1D18A9856A87
  last_name: Sazanov
  orcid: 0000-0002-0977-7989
citation:
  ama: Letts JA, Degliesposti G, Fiedorczuk K, Skehel M, Sazanov LA. Purification
    of ovine respiratory complex i results in a highly active and stable preparation.
    <i>Journal of Biological Chemistry</i>. 2016;291(47):24657-24675. doi:<a href="https://doi.org/10.1074/jbc.M116.735142">10.1074/jbc.M116.735142</a>
  apa: Letts, J. A., Degliesposti, G., Fiedorczuk, K., Skehel, M., &#38; Sazanov,
    L. A. (2016). Purification of ovine respiratory complex i results in a highly
    active and stable preparation. <i>Journal of Biological Chemistry</i>. American
    Society for Biochemistry and Molecular Biology. <a href="https://doi.org/10.1074/jbc.M116.735142">https://doi.org/10.1074/jbc.M116.735142</a>
  chicago: Letts, James A, Gianluca Degliesposti, Karol Fiedorczuk, Mark Skehel, and
    Leonid A Sazanov. “Purification of Ovine Respiratory Complex i Results in a Highly
    Active and Stable Preparation.” <i>Journal of Biological Chemistry</i>. American
    Society for Biochemistry and Molecular Biology, 2016. <a href="https://doi.org/10.1074/jbc.M116.735142">https://doi.org/10.1074/jbc.M116.735142</a>.
  ieee: J. A. Letts, G. Degliesposti, K. Fiedorczuk, M. Skehel, and L. A. Sazanov,
    “Purification of ovine respiratory complex i results in a highly active and stable
    preparation,” <i>Journal of Biological Chemistry</i>, vol. 291, no. 47. American
    Society for Biochemistry and Molecular Biology, pp. 24657–24675, 2016.
  ista: Letts JA, Degliesposti G, Fiedorczuk K, Skehel M, Sazanov LA. 2016. Purification
    of ovine respiratory complex i results in a highly active and stable preparation.
    Journal of Biological Chemistry. 291(47), 24657–24675.
  mla: Letts, James A., et al. “Purification of Ovine Respiratory Complex i Results
    in a Highly Active and Stable Preparation.” <i>Journal of Biological Chemistry</i>,
    vol. 291, no. 47, American Society for Biochemistry and Molecular Biology, 2016,
    pp. 24657–75, doi:<a href="https://doi.org/10.1074/jbc.M116.735142">10.1074/jbc.M116.735142</a>.
  short: J.A. Letts, G. Degliesposti, K. Fiedorczuk, M. Skehel, L.A. Sazanov, Journal
    of Biological Chemistry 291 (2016) 24657–24675.
date_created: 2018-12-11T11:50:44Z
date_published: 2016-11-18T00:00:00Z
date_updated: 2021-01-12T06:49:06Z
day: '18'
department:
- _id: LeSa
doi: 10.1074/jbc.M116.735142
ec_funded: 1
intvolume: '       291'
issue: '47'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5114416/
month: '11'
oa: 1
oa_version: Submitted Version
page: 24657 - 24675
project:
- _id: 2593EBD6-B435-11E9-9278-68D0E5697425
  name: Atomic-Resolution Structures of Mitochondrial Respiratory Chain Supercomplexes
    (FEBS)
- _id: 2590DB08-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '701309'
  name: Atomic-Resolution Structures of Mitochondrial Respiratory Chain Supercomplexes
    (H2020)
publication: Journal of Biological Chemistry
publication_status: published
publisher: American Society for Biochemistry and Molecular Biology
publist_id: '6139'
quality_controlled: '1'
scopus_import: 1
status: public
title: Purification of ovine respiratory complex i results in a highly active and
  stable preparation
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 291
year: '2016'
...
---
_id: '1226'
abstract:
- lang: eng
  text: Mitochondrial complex I (also known as NADH:ubiquinone oxidoreductase) contributes
    to cellular energy production by transferring electrons from NADH to ubiquinone
    coupled to proton translocation across the membrane. It is the largest protein
    assembly of the respiratory chain with a total mass of 970 kilodaltons. Here we
    present a nearly complete atomic structure of ovine (Ovis aries) mitochondrial
    complex I at 3.9 Å resolution, solved by cryo-electron microscopy with cross-linking
    and mass-spectrometry mapping experiments. All 14 conserved core subunits and
    31 mitochondria-specific supernumerary subunits are resolved within the L-shaped
    molecule. The hydrophilic matrix arm comprises flavin mononucleotide and 8 iron-sulfur
    clusters involved in electron transfer, and the membrane arm contains 78 transmembrane
    helices, mostly contributed by antiporter-like subunits involved in proton translocation.
    Supernumerary subunits form an interlinked, stabilizing shell around the conserved
    core. Tightly bound lipids (including cardiolipins) further stabilize interactions
    between the hydrophobic subunits. Subunits with possible regulatory roles contain
    additional cofactors, NADPH and two phosphopantetheine molecules, which are shown
    to be involved in inter-subunit interactions. We observe two different conformations
    of the complex, which may be related to the conformationally driven coupling mechanism
    and to the active-deactive transition of the enzyme. Our structure provides insight
    into the mechanism, assembly, maturation and dysfunction of mitochondrial complex
    I, and allows detailed molecular analysis of disease-causing mutations.
article_processing_charge: No
article_type: original
author:
- first_name: Karol
  full_name: Fiedorczuk, Karol
  id: 5BFF67CE-02D1-11E9-B11A-A5A4D7DFFFD0
  last_name: Fiedorczuk
- first_name: James A
  full_name: Letts, James A
  id: 322DA418-F248-11E8-B48F-1D18A9856A87
  last_name: Letts
  orcid: 0000-0002-9864-3586
- first_name: Gianluca
  full_name: Degliesposti, Gianluca
  last_name: Degliesposti
- first_name: Karol
  full_name: Kaszuba, Karol
  id: 3FDF9472-F248-11E8-B48F-1D18A9856A87
  last_name: Kaszuba
- first_name: Mark
  full_name: Skehel, Mark
  last_name: Skehel
- first_name: Leonid A
  full_name: Sazanov, Leonid A
  id: 338D39FE-F248-11E8-B48F-1D18A9856A87
  last_name: Sazanov
  orcid: 0000-0002-0977-7989
citation:
  ama: Fiedorczuk K, Letts JA, Degliesposti G, Kaszuba K, Skehel M, Sazanov LA. Atomic
    structure of the entire mammalian mitochondrial complex i. <i>Nature</i>. 2016;538(7625):406-410.
    doi:<a href="https://doi.org/10.1038/nature19794">10.1038/nature19794</a>
  apa: Fiedorczuk, K., Letts, J. A., Degliesposti, G., Kaszuba, K., Skehel, M., &#38;
    Sazanov, L. A. (2016). Atomic structure of the entire mammalian mitochondrial
    complex i. <i>Nature</i>. Nature Publishing Group. <a href="https://doi.org/10.1038/nature19794">https://doi.org/10.1038/nature19794</a>
  chicago: Fiedorczuk, Karol, James A Letts, Gianluca Degliesposti, Karol Kaszuba,
    Mark Skehel, and Leonid A Sazanov. “Atomic Structure of the Entire Mammalian Mitochondrial
    Complex I.” <i>Nature</i>. Nature Publishing Group, 2016. <a href="https://doi.org/10.1038/nature19794">https://doi.org/10.1038/nature19794</a>.
  ieee: K. Fiedorczuk, J. A. Letts, G. Degliesposti, K. Kaszuba, M. Skehel, and L.
    A. Sazanov, “Atomic structure of the entire mammalian mitochondrial complex i,”
    <i>Nature</i>, vol. 538, no. 7625. Nature Publishing Group, pp. 406–410, 2016.
  ista: Fiedorczuk K, Letts JA, Degliesposti G, Kaszuba K, Skehel M, Sazanov LA. 2016.
    Atomic structure of the entire mammalian mitochondrial complex i. Nature. 538(7625),
    406–410.
  mla: Fiedorczuk, Karol, et al. “Atomic Structure of the Entire Mammalian Mitochondrial
    Complex I.” <i>Nature</i>, vol. 538, no. 7625, Nature Publishing Group, 2016,
    pp. 406–10, doi:<a href="https://doi.org/10.1038/nature19794">10.1038/nature19794</a>.
  short: K. Fiedorczuk, J.A. Letts, G. Degliesposti, K. Kaszuba, M. Skehel, L.A. Sazanov,
    Nature 538 (2016) 406–410.
date_created: 2018-12-11T11:50:49Z
date_published: 2016-10-20T00:00:00Z
date_updated: 2021-01-12T06:49:13Z
day: '20'
department:
- _id: LeSa
doi: 10.1038/nature19794
ec_funded: 1
external_id:
  pmid:
  - '27595392'
intvolume: '       538'
issue: '7625'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5164932/
month: '10'
oa: 1
oa_version: Submitted Version
page: 406 - 410
pmid: 1
project:
- _id: 2593EBD6-B435-11E9-9278-68D0E5697425
  name: Atomic-Resolution Structures of Mitochondrial Respiratory Chain Supercomplexes
    (FEBS)
- _id: 2590DB08-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '701309'
  name: Atomic-Resolution Structures of Mitochondrial Respiratory Chain Supercomplexes
    (H2020)
publication: Nature
publication_status: published
publisher: Nature Publishing Group
publist_id: '6108'
quality_controlled: '1'
scopus_import: 1
status: public
title: Atomic structure of the entire mammalian mitochondrial complex i
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 538
year: '2016'
...
---
_id: '1232'
abstract:
- lang: eng
  text: Mitochondrial electron transport chain complexes are organized into supercomplexes
    responsible for carrying out cellular respiration. Here we present three architectures
    of mammalian (ovine) supercomplexes determined by cryo-electron microscopy. We
    identify two distinct arrangements of supercomplex CICIII 2 CIV (the respirasome)
    - a major 'tight' form and a minor 'loose' form (resolved at the resolution of
    5.8 Å and 6.7 Å, respectively), which may represent different stages in supercomplex
    assembly or disassembly. We have also determined an architecture of supercomplex
    CICIII 2 at 7.8 Å resolution. All observed density can be attributed to the known
    80 subunits of the individual complexes, including 132 transmembrane helices.
    The individual complexes form tight interactions that vary between the architectures,
    with complex IV subunit COX7a switching contact from complex III to complex I.
    The arrangement of active sites within the supercomplex may help control reactive
    oxygen species production. To our knowledge, these are the first complete architectures
    of the dominant, physiologically relevant state of the electron transport chain.
acknowledgement: We thank the MRC LMB Cambridge for the use of the Titan Krios microscope.
  Data processing was performed using the IST high-performance computer cluster. J.A.L.
  holds a long-term fellowship from FEBS. K.F. is partially funded by a MRC UK PhD
  fellowship.
author:
- first_name: James A
  full_name: Letts, James A
  id: 322DA418-F248-11E8-B48F-1D18A9856A87
  last_name: Letts
  orcid: 0000-0002-9864-3586
- first_name: Karol
  full_name: Fiedorczuk, Karol
  id: 5BFF67CE-02D1-11E9-B11A-A5A4D7DFFFD0
  last_name: Fiedorczuk
- first_name: Leonid A
  full_name: Sazanov, Leonid A
  id: 338D39FE-F248-11E8-B48F-1D18A9856A87
  last_name: Sazanov
  orcid: 0000-0002-0977-7989
citation:
  ama: Letts JA, Fiedorczuk K, Sazanov LA. The architecture of respiratory supercomplexes.
    <i>Nature</i>. 2016;537(7622):644-648. doi:<a href="https://doi.org/10.1038/nature19774">10.1038/nature19774</a>
  apa: Letts, J. A., Fiedorczuk, K., &#38; Sazanov, L. A. (2016). The architecture
    of respiratory supercomplexes. <i>Nature</i>. Nature Publishing Group. <a href="https://doi.org/10.1038/nature19774">https://doi.org/10.1038/nature19774</a>
  chicago: Letts, James A, Karol Fiedorczuk, and Leonid A Sazanov. “The Architecture
    of Respiratory Supercomplexes.” <i>Nature</i>. Nature Publishing Group, 2016.
    <a href="https://doi.org/10.1038/nature19774">https://doi.org/10.1038/nature19774</a>.
  ieee: J. A. Letts, K. Fiedorczuk, and L. A. Sazanov, “The architecture of respiratory
    supercomplexes,” <i>Nature</i>, vol. 537, no. 7622. Nature Publishing Group, pp.
    644–648, 2016.
  ista: Letts JA, Fiedorczuk K, Sazanov LA. 2016. The architecture of respiratory
    supercomplexes. Nature. 537(7622), 644–648.
  mla: Letts, James A., et al. “The Architecture of Respiratory Supercomplexes.” <i>Nature</i>,
    vol. 537, no. 7622, Nature Publishing Group, 2016, pp. 644–48, doi:<a href="https://doi.org/10.1038/nature19774">10.1038/nature19774</a>.
  short: J.A. Letts, K. Fiedorczuk, L.A. Sazanov, Nature 537 (2016) 644–648.
date_created: 2018-12-11T11:50:51Z
date_published: 2016-09-29T00:00:00Z
date_updated: 2021-01-12T06:49:16Z
day: '29'
department:
- _id: LeSa
doi: 10.1038/nature19774
intvolume: '       537'
issue: '7622'
language:
- iso: eng
month: '09'
oa_version: None
page: 644 - 648
project:
- _id: 2593EBD6-B435-11E9-9278-68D0E5697425
  name: Atomic-Resolution Structures of Mitochondrial Respiratory Chain Supercomplexes
    (FEBS)
publication: Nature
publication_status: published
publisher: Nature Publishing Group
publist_id: '6102'
quality_controlled: '1'
scopus_import: 1
status: public
title: The architecture of respiratory supercomplexes
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 537
year: '2016'
...