Effects of x-ray free-electron laser pulse intensity on the Mn K β 1,3x-ray emission spectrum in photosystem II - A case study for metalloprotein crystals and solutions
(2021) In Structural Dynamics 8(6).- Abstract
In the last ten years, x-ray free-electron lasers (XFELs) have been successfully employed to characterize metalloproteins at room temperature using various techniques including x-ray diffraction, scattering, and spectroscopy. The approach has been to outrun the radiation damage by using femtosecond (fs) x-ray pulses. An example of an important and damage sensitive active metal center is the Mn4CaO5 cluster in photosystem II (PS II), the catalytic site of photosynthetic water oxidation. The combination of serial femtosecond x-ray crystallography and Kβ x-ray emission spectroscopy (XES) has proven to be a powerful multimodal approach for simultaneously probing the overall protein structure and the electronic state of the Mn4CaO5 cluster... (More)
In the last ten years, x-ray free-electron lasers (XFELs) have been successfully employed to characterize metalloproteins at room temperature using various techniques including x-ray diffraction, scattering, and spectroscopy. The approach has been to outrun the radiation damage by using femtosecond (fs) x-ray pulses. An example of an important and damage sensitive active metal center is the Mn4CaO5 cluster in photosystem II (PS II), the catalytic site of photosynthetic water oxidation. The combination of serial femtosecond x-ray crystallography and Kβ x-ray emission spectroscopy (XES) has proven to be a powerful multimodal approach for simultaneously probing the overall protein structure and the electronic state of the Mn4CaO5 cluster throughout the catalytic (Kok) cycle. As the observed spectral changes in the Mn4CaO5 cluster are very subtle, it is critical to consider the potential effects of the intense XFEL pulses on the Kβ XES signal. We report here a systematic study of the effects of XFEL peak power, beam focus, and dose on the Mn Kβ1,3 XES spectra in PS II over a wide range of pulse parameters collected over seven different experimental runs using both microcrystal and solution PS II samples. Our findings show that for beam intensities ranging from ∼5 × 1015 to 5 × 1017 W/cm2 at a pulse length of ∼35 fs, the spectral effects are small compared to those observed between S-states in the Kok cycle. Our results provide a benchmark for other XFEL-based XES studies on metalloproteins, confirming the viability of this approach.
(Less)
- author
- organization
- publishing date
- 2021-11-01
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Structural Dynamics
- volume
- 8
- issue
- 6
- article number
- 064302
- publisher
- American Institute of Physics (AIP)
- external identifiers
-
- pmid:34849380
- scopus:85120068938
- ISSN
- 2329-7778
- DOI
- 10.1063/4.0000130
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2021 Author(s).
- id
- a5416ce3-bd02-4b87-a78f-df4ceeaad078
- date added to LUP
- 2022-01-24 08:40:34
- date last changed
- 2024-06-30 01:18:20
@article{a5416ce3-bd02-4b87-a78f-df4ceeaad078,
abstract = {{<p>In the last ten years, x-ray free-electron lasers (XFELs) have been successfully employed to characterize metalloproteins at room temperature using various techniques including x-ray diffraction, scattering, and spectroscopy. The approach has been to outrun the radiation damage by using femtosecond (fs) x-ray pulses. An example of an important and damage sensitive active metal center is the Mn4CaO5 cluster in photosystem II (PS II), the catalytic site of photosynthetic water oxidation. The combination of serial femtosecond x-ray crystallography and Kβ x-ray emission spectroscopy (XES) has proven to be a powerful multimodal approach for simultaneously probing the overall protein structure and the electronic state of the Mn4CaO5 cluster throughout the catalytic (Kok) cycle. As the observed spectral changes in the Mn4CaO5 cluster are very subtle, it is critical to consider the potential effects of the intense XFEL pulses on the Kβ XES signal. We report here a systematic study of the effects of XFEL peak power, beam focus, and dose on the Mn Kβ1,3 XES spectra in PS II over a wide range of pulse parameters collected over seven different experimental runs using both microcrystal and solution PS II samples. Our findings show that for beam intensities ranging from ∼5 × 1015 to 5 × 1017 W/cm2 at a pulse length of ∼35 fs, the spectral effects are small compared to those observed between S-states in the Kok cycle. Our results provide a benchmark for other XFEL-based XES studies on metalloproteins, confirming the viability of this approach.</p>}},
author = {{Fransson, Thomas and Alonso-Mori, Roberto and Chatterjee, Ruchira and Cheah, Mun Hon and Ibrahim, Mohamed and Hussein, Rana and Zhang, Miao and Fuller, Franklin and Gul, Sheraz and Kim, In Sik and Simon, Philipp S. and Bogacz, Isabel and Makita, Hiroki and De Lichtenberg, Casper and Song, Sanghoon and Batyuk, Alexander and Sokaras, Dimosthenis and Massad, Ramzi and Doyle, Margaret and Britz, Alexander and Weninger, Clemens and Zouni, Athina and Messinger, Johannes and Yachandra, Vittal K. and Yano, Junko and Kern, Jan and Bergmann, Uwe}},
issn = {{2329-7778}},
language = {{eng}},
month = {{11}},
number = {{6}},
publisher = {{American Institute of Physics (AIP)}},
series = {{Structural Dynamics}},
title = {{Effects of x-ray free-electron laser pulse intensity on the Mn K β <sub>1,3</sub>x-ray emission spectrum in photosystem II - A case study for metalloprotein crystals and solutions}},
url = {{http://dx.doi.org/10.1063/4.0000130}},
doi = {{10.1063/4.0000130}},
volume = {{8}},
year = {{2021}},
}