---
_id: '8040'
abstract:
- lang: eng
  text: The mitochondrial respiratory chain, formed by five protein complexes, utilizes
    energy from catabolic processes to synthesize ATP. Complex I, the first and the
    largest protein complex of the chain, harvests electrons from NADH to reduce quinone,
    while pumping protons across the mitochondrial membrane. Detailed knowledge of
    the working principle of such coupled charge-transfer processes remains, however,
    fragmentary due to bottlenecks in understanding redox-driven conformational transitions
    and their interplay with the hydrated proton pathways. Complex I from Thermus
    thermophilus encases 16 subunits with nine iron–sulfur clusters, reduced by electrons
    from NADH. Here, employing the latest crystal structure of T. thermophilus complex
    I, we have used microsecond-scale molecular dynamics simulations to study the
    chemo-mechanical coupling between redox changes of the iron–sulfur clusters and
    conformational transitions across complex I. First, we identify the redox switches
    within complex I, which allosterically couple the dynamics of the quinone binding
    pocket to the site of NADH reduction. Second, our free-energy calculations reveal
    that the affinity of the quinone, specifically menaquinone, for the binding-site
    is higher than that of its reduced, menaquinol form—a design essential for menaquinol
    release. Remarkably, the barriers to diffusive menaquinone dynamics are lesser
    than that of the more ubiquitous ubiquinone, and the naphthoquinone headgroup
    of the former furnishes stronger binding interactions with the pocket, favoring
    menaquinone for charge transport in T. thermophilus. Our computations are consistent
    with experimentally validated mutations and hierarchize the key residues into
    three functional classes, identifying new mutation targets. Third, long-range
    hydrogen-bond networks connecting the quinone-binding site to the transmembrane
    subunits are found to be responsible for proton pumping. Put together, the simulations
    reveal the molecular design principles linking redox reactions to quinone turnover
    to proton translocation in complex I.
article_processing_charge: No
article_type: original
author:
- first_name: Chitrak
  full_name: Gupta, Chitrak
  last_name: Gupta
- first_name: Umesh
  full_name: Khaniya, Umesh
  last_name: Khaniya
- first_name: Chun Kit
  full_name: Chan, Chun Kit
  last_name: Chan
- first_name: Francois
  full_name: Dehez, Francois
  last_name: Dehez
- first_name: Mrinal
  full_name: Shekhar, Mrinal
  last_name: Shekhar
- first_name: M. R.
  full_name: Gunner, M. R.
  last_name: Gunner
- first_name: Leonid A
  full_name: Sazanov, Leonid A
  id: 338D39FE-F248-11E8-B48F-1D18A9856A87
  last_name: Sazanov
  orcid: 0000-0002-0977-7989
- first_name: Christophe
  full_name: Chipot, Christophe
  last_name: Chipot
- first_name: Abhishek
  full_name: Singharoy, Abhishek
  last_name: Singharoy
citation:
  ama: Gupta C, Khaniya U, Chan CK, et al. Charge transfer and chemo-mechanical coupling
    in respiratory complex I. <i>Journal of the American Chemical Society</i>. 2020;142(20):9220-9230.
    doi:<a href="https://doi.org/10.1021/jacs.9b13450">10.1021/jacs.9b13450</a>
  apa: Gupta, C., Khaniya, U., Chan, C. K., Dehez, F., Shekhar, M., Gunner, M. R.,
    … Singharoy, A. (2020). Charge transfer and chemo-mechanical coupling in respiratory
    complex I. <i>Journal of the American Chemical Society</i>. American Chemical
    Society. <a href="https://doi.org/10.1021/jacs.9b13450">https://doi.org/10.1021/jacs.9b13450</a>
  chicago: Gupta, Chitrak, Umesh Khaniya, Chun Kit Chan, Francois Dehez, Mrinal Shekhar,
    M. R. Gunner, Leonid A Sazanov, Christophe Chipot, and Abhishek Singharoy. “Charge
    Transfer and Chemo-Mechanical Coupling in Respiratory Complex I.” <i>Journal of
    the American Chemical Society</i>. American Chemical Society, 2020. <a href="https://doi.org/10.1021/jacs.9b13450">https://doi.org/10.1021/jacs.9b13450</a>.
  ieee: C. Gupta <i>et al.</i>, “Charge transfer and chemo-mechanical coupling in
    respiratory complex I,” <i>Journal of the American Chemical Society</i>, vol.
    142, no. 20. American Chemical Society, pp. 9220–9230, 2020.
  ista: Gupta C, Khaniya U, Chan CK, Dehez F, Shekhar M, Gunner MR, Sazanov LA, Chipot
    C, Singharoy A. 2020. Charge transfer and chemo-mechanical coupling in respiratory
    complex I. Journal of the American Chemical Society. 142(20), 9220–9230.
  mla: Gupta, Chitrak, et al. “Charge Transfer and Chemo-Mechanical Coupling in Respiratory
    Complex I.” <i>Journal of the American Chemical Society</i>, vol. 142, no. 20,
    American Chemical Society, 2020, pp. 9220–30, doi:<a href="https://doi.org/10.1021/jacs.9b13450">10.1021/jacs.9b13450</a>.
  short: C. Gupta, U. Khaniya, C.K. Chan, F. Dehez, M. Shekhar, M.R. Gunner, L.A.
    Sazanov, C. Chipot, A. Singharoy, Journal of the American Chemical Society 142
    (2020) 9220–9230.
date_created: 2020-06-29T07:59:35Z
date_published: 2020-05-20T00:00:00Z
date_updated: 2023-08-22T07:49:38Z
day: '20'
department:
- _id: LeSa
doi: 10.1021/jacs.9b13450
external_id:
  isi:
  - '000537415600020'
  pmid:
  - '32347721'
intvolume: '       142'
isi: 1
issue: '20'
language:
- iso: eng
month: '05'
oa_version: None
page: 9220-9230
pmid: 1
publication: Journal of the American Chemical Society
publication_identifier:
  eissn:
  - '15205126'
  issn:
  - '00027863'
publication_status: published
publisher: American Chemical Society
quality_controlled: '1'
related_material:
  record:
  - id: '9326'
    relation: research_data
    status: public
  - id: '9713'
    relation: research_data
    status: public
  - id: '9878'
    relation: research_data
    status: public
scopus_import: '1'
status: public
title: Charge transfer and chemo-mechanical coupling in respiratory complex I
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 142
year: '2020'
...
---
_id: '9167'
abstract:
- lang: eng
  text: We introduce a self-propelled colloidal hematite docker that can be steered
    to a small particle cargo many times its size, dock, transport the cargo to a
    remote location, and then release it. The self-propulsion and docking are reversible
    and activated by visible light. The docker can be steered either by a weak uniform
    magnetic field or by nanoscale tracks in a textured substrate. The light-activated
    motion and docking originate from osmotic/phoretic particle transport in a concentration
    gradient of fuel, hydrogen peroxide, induced by the photocatalytic activity of
    the hematite. The docking mechanism is versatile and can be applied to various
    materials and shapes. The hematite dockers are simple single-component particles
    and are synthesized in bulk quantities. This system opens up new possibilities
    for designing complex micrometer-size factories as well as new biomimetic systems.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Jérémie A
  full_name: Palacci, Jérémie A
  id: 8fb92548-2b22-11eb-b7c1-a3f0d08d7c7d
  last_name: Palacci
  orcid: 0000-0002-7253-9465
- first_name: Stefano
  full_name: Sacanna, Stefano
  last_name: Sacanna
- first_name: Adrian
  full_name: Vatchinsky, Adrian
  last_name: Vatchinsky
- first_name: Paul M.
  full_name: Chaikin, Paul M.
  last_name: Chaikin
- first_name: David J.
  full_name: Pine, David J.
  last_name: Pine
citation:
  ama: Palacci JA, Sacanna S, Vatchinsky A, Chaikin PM, Pine DJ. Photoactivated colloidal
    dockers for cargo transportation. <i>Journal of the American Chemical Society</i>.
    2013;135(43):15978-15981. doi:<a href="https://doi.org/10.1021/ja406090s">10.1021/ja406090s</a>
  apa: Palacci, J. A., Sacanna, S., Vatchinsky, A., Chaikin, P. M., &#38; Pine, D.
    J. (2013). Photoactivated colloidal dockers for cargo transportation. <i>Journal
    of the American Chemical Society</i>. American Chemical Society. <a href="https://doi.org/10.1021/ja406090s">https://doi.org/10.1021/ja406090s</a>
  chicago: Palacci, Jérémie A, Stefano Sacanna, Adrian Vatchinsky, Paul M. Chaikin,
    and David J. Pine. “Photoactivated Colloidal Dockers for Cargo Transportation.”
    <i>Journal of the American Chemical Society</i>. American Chemical Society, 2013.
    <a href="https://doi.org/10.1021/ja406090s">https://doi.org/10.1021/ja406090s</a>.
  ieee: J. A. Palacci, S. Sacanna, A. Vatchinsky, P. M. Chaikin, and D. J. Pine, “Photoactivated
    colloidal dockers for cargo transportation,” <i>Journal of the American Chemical
    Society</i>, vol. 135, no. 43. American Chemical Society, pp. 15978–15981, 2013.
  ista: Palacci JA, Sacanna S, Vatchinsky A, Chaikin PM, Pine DJ. 2013. Photoactivated
    colloidal dockers for cargo transportation. Journal of the American Chemical Society.
    135(43), 15978–15981.
  mla: Palacci, Jérémie A., et al. “Photoactivated Colloidal Dockers for Cargo Transportation.”
    <i>Journal of the American Chemical Society</i>, vol. 135, no. 43, American Chemical
    Society, 2013, pp. 15978–81, doi:<a href="https://doi.org/10.1021/ja406090s">10.1021/ja406090s</a>.
  short: J.A. Palacci, S. Sacanna, A. Vatchinsky, P.M. Chaikin, D.J. Pine, Journal
    of the American Chemical Society 135 (2013) 15978–15981.
date_created: 2021-02-18T14:31:26Z
date_published: 2013-10-30T00:00:00Z
date_updated: 2021-02-22T10:10:41Z
day: '30'
doi: 10.1021/ja406090s
extern: '1'
external_id:
  arxiv:
  - '1310.5724'
  pmid:
  - '24131488'
intvolume: '       135'
issue: '43'
keyword:
- Colloid and Surface Chemistry
- Biochemistry
- General Chemistry
- Catalysis
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1310.5724
month: '10'
oa: 1
oa_version: Preprint
page: 15978-15981
pmid: 1
publication: Journal of the American Chemical Society
publication_identifier:
  eissn:
  - '15205126'
  issn:
  - '00027863'
publication_status: published
publisher: American Chemical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Photoactivated colloidal dockers for cargo transportation
type: journal_article
user_id: D865714E-FA4E-11E9-B85B-F5C5E5697425
volume: 135
year: '2013'
...