The role of axial ligands for the structure and function of chlorophylls
Heimdal, Jimmy LU ; Jensen, Kasper LU ; Devarajan, Ajitha LU and Ryde, Ulf LU
(2007)
In Journal of Biological Inorganic Chemistry
12(1).
p.49-61
- Abstract
- We have studied the effect of axial ligation of chlorophyll and bacteriochlorophyll using density functional calculations. Eleven different axial ligands have been considered, including models of histidine, aspartate/glutamate, asparagine/glutamine, serine, tyrosine, methionine, water, the protein backbone, and phosphate. The native chlorophylls, as well as their cation and anion radical states and models of the reaction centres P680 and P700, have been studied and we have compared the geometries, binding energies, reduction potentials, and absorption spectra. Our results clearly show that the chlorophylls strongly prefer to be five-coordinate, in accordance with available crystal structures. The axial ligands decrease the reduction... (More)
- We have studied the effect of axial ligation of chlorophyll and bacteriochlorophyll using density functional calculations. Eleven different axial ligands have been considered, including models of histidine, aspartate/glutamate, asparagine/glutamine, serine, tyrosine, methionine, water, the protein backbone, and phosphate. The native chlorophylls, as well as their cation and anion radical states and models of the reaction centres P680 and P700, have been studied and we have compared the geometries, binding energies, reduction potentials, and absorption spectra. Our results clearly show that the chlorophylls strongly prefer to be five-coordinate, in accordance with available crystal structures. The axial ligands decrease the reduction potentials, so they cannot explain the high potential of P680. They also redshift the Q band, but not enough to explain the occurrence of red chlorophylls. However, there is some relation between the axial ligands and their location in the various photosynthetic proteins. In particular, the intrinsic reduction potential of the second molecule in the electron transfer path is always lower than that of the third one, a feature that may prevent back-transfer of the electron. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/685162
- author
- Heimdal, Jimmy
LU
; Jensen, Kasper
LU
; Devarajan, Ajitha
LU
and Ryde, Ulf
LU
- organization
- publishing date
- 2007
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- density functional theory, axial ligands, chlorophyll, photosynthesis, reduction potential
- in
- Journal of Biological Inorganic Chemistry
- volume
- 12
- issue
- 1
- pages
- 49 - 61
- publisher
- Springer
- external identifiers
-
- wos:000242462600005
- scopus:33845362034
- pmid:16953415
- ISSN
- 1432-1327
- DOI
- 10.1007/s00775-006-0164-z
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Theoretical Chemistry (S) (011001039)
- id
- be4a0a6c-e618-4551-ad2d-ff1b24600a87 (old id 685162)
- date added to LUP
- 2016-04-01 12:35:59
- date last changed
- 2023-01-24 02:30:46
@article{be4a0a6c-e618-4551-ad2d-ff1b24600a87,
abstract = {{We have studied the effect of axial ligation of chlorophyll and bacteriochlorophyll using density functional calculations. Eleven different axial ligands have been considered, including models of histidine, aspartate/glutamate, asparagine/glutamine, serine, tyrosine, methionine, water, the protein backbone, and phosphate. The native chlorophylls, as well as their cation and anion radical states and models of the reaction centres P680 and P700, have been studied and we have compared the geometries, binding energies, reduction potentials, and absorption spectra. Our results clearly show that the chlorophylls strongly prefer to be five-coordinate, in accordance with available crystal structures. The axial ligands decrease the reduction potentials, so they cannot explain the high potential of P680. They also redshift the Q band, but not enough to explain the occurrence of red chlorophylls. However, there is some relation between the axial ligands and their location in the various photosynthetic proteins. In particular, the intrinsic reduction potential of the second molecule in the electron transfer path is always lower than that of the third one, a feature that may prevent back-transfer of the electron.}},
author = {{Heimdal, Jimmy and Jensen, Kasper and Devarajan, Ajitha and Ryde, Ulf}},
issn = {{1432-1327}},
keywords = {{density functional theory; axial ligands; chlorophyll; photosynthesis; reduction potential}},
language = {{eng}},
number = {{1}},
pages = {{49--61}},
publisher = {{Springer}},
series = {{Journal of Biological Inorganic Chemistry}},
title = {{The role of axial ligands for the structure and function of chlorophylls}},
url = {{https://lup.lub.lu.se/search/files/135493955/93_chl.pdf}},
doi = {{10.1007/s00775-006-0164-z}},
volume = {{12}},
year = {{2007}},
}