Serena DeBeer

from Wikipedia, the free encyclopedia

Serena DeBeer (born 1973 ) is an American chemist . She is currently a W3 Professor and Director at the Max Planck Institute for Chemical Energy Conversion in Mülheim an der Ruhr , Germany, where she heads the Department of Inorganic Spectroscopy. Her expertise lies in the development and application of X-ray spectroscopic methods to elucidate the electronic structure of biological and chemical catalysts .

Education and career

Serena DeBeer studied at Southwestern University in Georgetown , Texas, USA, where she completed her bachelor's degree in chemistry with mathematics as a minor with distinction in 1995 . She received her PhD from Stanford University in 2002 under the supervision of Edward I. Solomon and Keith O. Hodgson. From 2001 to 2003 she worked as a beamline scientist at the Stanford Synchrotron Radiation Laboratory and later, until 2009, as a research assistant at the SLAC National Accelerator Laboratory . In the fall of 2009 she moved to Ithaca, New York , USA to work at Cornell University as an assistant professor in the Department of Chemistry and Chemical Biology. In summer 2011 she began her work as a W2 professor and research group leader at the Max Planck Institute for Bioinorganic Chemistry (renamed in 2012 to Max Planck Institute for Chemical Energy Conversion , MPI CEC) in Mülheim an der Ruhr . She has been an associate professor at Cornell University since 2012 and an honorary faculty member at the Ruhr University Bochum since 2014 . After DeBeer headed the “X-ray Spectroscopy” research group at the MPI CEC until 2017, she was appointed director at the same institute and promoted to a W3 professorship. She currently heads the “Inorganic Spectroscopy” department at the MPI CEC. In addition, she is group leader of the PINK Strahllinien project at the Energy Materials In-Situ Laboratory of the Helmholtz Center Berlin for Materials and Energy .

research

The DeBeer group deals with fundamental questions in energy research, namely how exactly energy in the form of chemical bonds can be reversibly stored and released with the help of transition metals that are present in large quantities on earth; and further, how this works as efficiently as possible. Her research group investigates homogeneous, heterogeneous as well as biological catalysts to find answers to these questions, with the focus primarily on enzymatic catalysis. Serena DeBeer is an expert in using advanced X-ray spectroscopy to understand catalytic transformations.

Nitrogenase

The main focus of her research lies in the investigation of the enzyme that is responsible for the conversion of nitrogen (N 2 ) into ammonia (NH 3 ) - nitrogenase . Serena DeBeer and her group are investigating this extraordinary system, which houses a FeMo cofactor (FeMoco) in its active center, as well as simpler model complexes with high-resolution X - ray absorption (XAS) and emission spectroscopy (XES). This work contributed significantly to the understanding of this active center. An essential contribution to this was the identification of the central atom in the active center, which is a carbide. In addition, the application of high-resolution XAS, supported by theoretical calculations, enabled her to determine the oxidation state of the Mo atom in FeMoco as Mo (III). This study was later investigations by Röntgendichroismusspektroskopie supplemented (X-ray Magnetic Circular Dichroism, "XMCD") in which experimental evidence for a non-dog spin configuration was found. Comparative studies of different nitrogenase enzymes with FeMoco and FeVco in the active centers, as well as Se-doped FeMoco and the spectroscopic characterization of the first intermediate state in the nitrogenase catalytic cycle (E 1 ) provide another approach to this research field .

Methane monooxygenase

Another important chemical conversion that is being investigated in the DeBeer group is the catalytic oxidation of methane to methanol . In nature, this process takes place with the help of the enzyme class of methane monooxygenases (MMOs). The active center of these enzymes, which enables the cleavage of a CH bond in methane, is the dinuclear Fe (IV) intermediate Q and occurs in the hydroxylase subunit (MMOH) in MMO. Spectroscopic studies by the DeBeer group have provided new insights into the structure of this dinuclear Fe complex. By applying advanced X-ray spectroscopic investigations, such as high-resolution XAS , the main intermediate in the biological methane oxidation was characterized, which turned out to be an acyclic dinuclear Fe structure (with an Fe (IV) = O unit). EXAFS studies additionally supported this finding by showing that there is no evidence of a short Fe-Fe bond, but rather a comparatively large distance between the two atoms, which is consistent with an acyclic structure.

Spectroscopic method development

Current activities of the DeBeer group include increasing the amount of information gained from the various X-ray spectroscopic methods that are also used to research biological catalysts.

These methods include:

Valence electron X-ray emission spectroscopy

With this method, which is also called VtC XES (valence-to-core X-ray emission spectroscopy), the X-ray fluorescence is measured, which occurs when a valence electron fills the gap in the 1s orbital caused by ionization. VtC XES thus enables the ionization energies of ligands to be determined and also provides information about the nature and degree of protonation of the ligand. A prominent example for the application of this method is the identification of a central carbon atom in the FeMo cofactor of nitrogenase (see section: Nitrogenase ).

Resonant valence electron X-ray emission spectroscopy ("RXES", also "Resonant Inelastic X-ray Scattering", "RIXS")

The DeBeer group is actively involved in the development and application of RXES / RIXS-based methods in the field of hard and soft X-rays. These include the 1s valence RIXS to determine ligand-selective XAS and the 2p3d RIXS to determine dd transitions.

Circular magnetic X-ray dichroism spectroscopy (X-ray Magnetic Circular Dichroism, "XMCD")

This method has been widely used for a long time to determine the magnetic properties of solids. In contrast, previous applications to (bio) inorganic systems or proteins have only been interpreted inadequately in terms of quality and quantity. The DeBeer group, on the other hand, succeeded in gaining essential information about covalent systems using XMCD. To date, it remains the only method with which a proof for the postulated non-dog configuration of the central Mo atom of nitrogenase could be produced (see section: Nitrogenase).

Instrumental equipment

Dispersive X-ray emission spectrometer for the laboratory

Serena DeBeer's group has developed an in-house dispersive X-ray emission spectrometer in collaboration with Prof. Birgit Kangießer's group ( TU Berlin ). It is based on a laboratory X-ray source (Metal Jet), combined with HAPG crystals (highly annealed pyrolytic graphite) and a CCD detector in a von Hamos arrangement. Spectra can thus be recorded in a range of 2.4-9.0 keV. For samples with a higher concentration, this spectrometer is an alternative to synchrotron-based beam lines.

PINK beam line

The DeBeer Group leads the development of the PINK beam line at the Energy Materials In-situ Laboratory of the Helmholtz Center Berlin for Materials and Energy . Dr. Sergey Peredkov is mainly responsible for planning and instrumentation. This beam line can be operated at energies of 2-10 keV, either in "pink" beam mode with a multilayer mirror, or as a monochromatic beam (by adding a double crystal monochromator ). The beamline is currently being commissioned.

Awards and recognitions

  • European Research Council (English E uropean R esearch C ouncil, ERC ) Synergy Grant for the project: Unraveling the secrets of Cu-based catalysts for CH activation (CUBE). In collaboration with scientists from the University of Oslo ( Norway ), University of Environmental and Life Sciences (Norway) and the University of Turin ( Italy ) (2019)
  • Associate Editor for Chemical Science (since 2018)
  • Inorganic Chemistry Lectureship Award (2016)
  • Society of Biological Inorganic Chemistry (SBIC), Early Career Award (2015)
  • European Research Council (ERC) Consolidator Grant for the project: Spectroscopic Studies of N 2 Reduction: From Biological to Heterogeneous Catalysis (N2ase) (2013)
  • Kavli Fellow, US National Academy of Sciences (2012)
  • Alfred P. Sloan Research Fellow (2011-2013)

Individual evidence

  1. ↑ Serena DeBeer | Chemistry & Chemical Biology Cornell Arts & Sciences. Retrieved March 20, 2020 .
  2. ↑ Honorary professor at RUB is the new director. Retrieved March 20, 2020 .
  3. ↑ Inorganic Spectroscopy | MPI CEC. Retrieved March 20, 2020 .
  4. ↑ a b Helmholtz Center Berlin for Materials and Energy: PINK. Retrieved March 20, 2020 (UK English).
  5. ↑ a b Helmholtz Center Berlin for Materials and Energy: Energy Materials In-Situ Laboratory Berlin. Retrieved March 20, 2020 (UK English).
  6. ↑ a b Kyle M. Lancaster, Michael Roemelt, Patrick Ettenhuber, Yilin Hu, Markus W. Ribbe: X-ray Emission Spectroscopy Evidences a Central Carbon in the Nitrogenase Iron-Molybdenum Cofactor . In: Science (New York, NY) . tape 334 , no. 6058 , November 18, 2011, ISSN  0036-8075 , p. 974–977 , doi : 10.1126 / science.1206445 (PMC = 3800678 [accessed March 20, 2020]).
  7. ^ Ragnar Bjornsson, Frederico A. Lima, Thomas Spatzal, Thomas Weyhermüller, Pieter Glatzel: Identification of a spin-coupled Mo (iii) in the nitrogenase iron – molybdenum cofactor . In: Chem. Sci. tape 5 , no. 8 , 2014, ISSN  2041-6520 , p. 3096-3103 , doi : 10.1039 / C4SC00337C ( rsc.org [accessed March 20, 2020]).
  8. ↑ a b Joanna K. Kowalska, Justin T. Henthorn, Casey Van Stappen, Christian Trncik, Oliver Einsle: X ‐ ray Magnetic Circular Dichroism Spectroscopy Applied to Nitrogenase and Related Models: Experimental Evidence for a Spin ‐ Coupled Molybdenum (III) Center . In: Angewandte Chemie International Edition . tape 58 , no. 28 , July 8, 2019, ISSN  1433-7851 , p. 9373-9377 , doi : 10.1002 / anie.201901899 , PMID 31119827 , PMC 6772009 (free full text) - (PMC = 6772009 [accessed March 20, 2020]).
  9. ^ Julian A. Rees, Ragnar Bjornsson, Joanna K. Kowalska, Frederico A. Lima, Julia Schlesier: Comparative electronic structures of nitrogenase FeMoco and FeVco . In: Dalton Transactions . tape 46 , no. 8 , 2017, ISSN  1477-9226 , p. 2445–2455 , doi : 10.1039 / C7DT00128B , PMID 28154874 , PMC 5322470 (free full text) - ( rsc.org [accessed March 20, 2020]).
  10. ↑ Justin T. Henthorn, Renee J. Arias, Sergey Koroidov, Thomas Kroll, Dimosthenis Sokaras: Localized Electronic Structure of Nitrogenase FeMoco Revealed by Selenium K-Edge High Resolution X-ray Absorption Spectroscopy . In: Journal of the American Chemical Society . tape 141 , no. 34 , August 28, 2019, ISSN  0002-7863 , p. 13676–13688 , doi : 10.1021 / jacs.9b06988 , PMID 31356071 , PMC 6716209 (free full text) - ( acs.org [accessed March 20, 2020]).
  11. ↑ Casey Van Stappen, Albert Thor Thorhallsson, Laure Decamps, Ragnar Bjornsson, Serena DeBeer: Resolving the structure of the E 1 state of Mo nitrogenase through Mo and Fe K-edge EXAFS and QM / MM calculations . In: Chemical Science . tape 10 , no. 42 , 2019, ISSN  2041-6520 , p. 9807-9821 , doi : 10.1039 / C9SC02187F , PMID 32055350 , PMC 6984330 (free full text) - ( rsc.org [accessed March 20, 2020]).
  12. ^ Casey Van Stappen, Roman Davydov, Zhi-Yong Yang, Ruixi Fan, Yisong Guo: Spectroscopic Description of the E 1 State of Mo Nitrogenase Based on Mo and Fe X-ray Absorption and Mössbauer Studies . In: Inorganic Chemistry . tape 58 , no. 18 , September 16, 2019, ISSN  0020-1669 , p. 12365-12376 , doi : 10.1021 / acs.inorgchem.9b01951 , PMID 31441651 , PMC 6751781 (free full text) - ( acs.org [accessed March 20, 2020]).
  13. ^ Rebeca G. Castillo, Rahul Banerjee, Caleb J. Allpress, Gregory T. Rohde, Eckhard Bill: High-Energy-Resolution Fluorescence-Detected X-ray Absorption of the Q Intermediate of Soluble Methane Monooxygenase . In: Journal of the American Chemical Society . tape 139 , no. 49 , December 13, 2017, ISSN  0002-7863 , p. 18024–18033 , doi : 10.1021 / jacs.7b09560 , PMID 29136468 , PMC 5729100 (free full text) - ( acs.org [accessed March 20, 2020]).
  14. ↑ George E. Cutsail, Rahul Banerjee, Ang Zhou, Lawrence Que, John D. Lipscomb: High-Resolution Extended X-ray Absorption Fine Structure Analysis Provides Evidence for a Longer Fe ··· Fe Distance in the Q Intermediate of Methane Monooxygenase . In: Journal of the American Chemical Society . tape 140 , no. 48 , December 5, 2018, ISSN  0002-7863 , p. 16807–16820 , doi : 10.1021 / jacs.8b10313 , PMID 30398343 , PMC 6470014 (free full text) - ( acs.org [accessed March 20, 2020]).
  15. ^ Eleanor R. Hall, Christopher J. Pollock, Jesper Bendix, Terrence J. Collins, Pieter Glatzel: Valence-to-Core-Detected X-ray Absorption Spectroscopy: Targeting Ligand Selectivity . In: Journal of the American Chemical Society . tape 136 , no. 28 , July 16, 2014, ISSN  0002-7863 , p. 10076–10084 , doi : 10.1021 / ja504206y ( acs.org [accessed March 20, 2020]).
  16. ^ Benjamin E. Van Kuiken, Anselm W. Hahn, Brahamjot Nayyar, Christine E. Schiewer, Sonny C. Lee: Electronic Spectra of Iron-Sulfur Complexes Measured by 2p3d RIXS Spectroscopy . In: Inorganic Chemistry . tape 57 , no. 12 , June 18, 2018, ISSN  0020-1669 , p. 7355-7361 , doi : 10.1021 / acs.inorgchem.8b01010 ( acs.org [accessed March 20, 2020]).
  17. ↑ Anselm W. Hahn, Benjamin E. Van Kuiken, Mustafa al Samarai, Mihail Atanasov, Thomas Weyhermüller: Measurement of the Ligand Field Spectra of Ferrous and Ferric Iron Chlorides Using 2p3d RIXS . In: Inorganic Chemistry . tape 56 , no. 14 , July 17, 2017, ISSN  0020-1669 , p. 8203-8211 , doi : 10.1021 / acs.inorgchem.7b00940 ( acs.org [accessed March 20, 2020]).
  18. Jump up ↑ Anselm W. Hahn, Benjamin E. Van Kuiken, Vijay Gopal Chilkuri, Natalia Levin, Eckhard Bill: Probing the Valence Electronic Structure of Low-Spin Ferrous and Ferric Complexes Using 2p3d Resonant Inelastic X-ray Scattering (RIXS) . In: Inorganic Chemistry . tape 57 , no. 15 , August 6, 2018, ISSN  0020-1669 , p. 9515-9530 , doi : 10.1021 / acs.inorgchem.8b01550 ( acs.org [accessed March 20, 2020]).
  19. ↑ Benjamin E. Van Kuiken, Anselm W. Hahn, Dimitrios Maganas, Serena DeBeer: Measuring Spin-Allowed and Spin-Forbidden d – d Excitations in Vanadium Complexes with 2p3d Resonant Inelastic X-ray Scattering . In: Inorganic Chemistry . tape 55 , no. 21 , November 7, 2016, ISSN  0020-1669 , p. 11497–11501 , doi : 10.1021 / acs.inorgchem.6b02053 ( acs.org [accessed March 20, 2020]).
  20. ↑ Dimitrios Maganas, Serena DeBeer, Frank Neese: A Restricted Open Configuration Interaction with Singles Method To Calculate Valence-to-Core Resonant X-ray Emission Spectra: A Case Study . In: Inorganic Chemistry . tape 56 , no. 19 , October 2, 2017, ISSN  0020-1669 , p. 11819–11836 , doi : 10.1021 / acs.inorgchem.7b01810 , PMID 28920680 , PMC 5692824 (free full text) - ( acs.org [accessed March 20, 2020]).
  21. ↑ Mustafa Al Samarai, Anselm W. Hahn, Abbas Beheshti Askari, Yi-Tao Cui, Kosuke Yamazoe: Elucidation of Structure – Activity Correlations in a Nickel Manganese Oxide Oxygen Evolution Reaction Catalyst by Operando Ni L-Edge X-ray Absorption Spectroscopy and 2p3d Resonant Inelastic X-ray Scattering . In: ACS Applied Materials & Interfaces . tape 11 , no. 42 , October 23, 2019, ISSN  1944-8244 , p. 38595-38605 , doi : 10.1021 / acsami.9b06752 ( acs.org [accessed March 20, 2020]).
  22. ↑ Joanna K. Kowalska, Brahamjot Nayyar, Julian A. Rees, Christine E. Schiewer, Sonny C. Lee: Iron L 2,3 -Edge X-ray Absorption and X-ray Magnetic Circular Dichroism Studies of Molecular Iron Complexes with Relevance to the FeMoco and FeVco Active Sites of Nitrogenase . In: Inorganic Chemistry . tape 56 , no. 14 , July 17, 2017, ISSN  0020-1669 , p. 8147-8158 , doi : 10.1021 / acs.inorgchem.7b00852 , PMID 28653855 , PMC 5516708 (free full text) - ( acs.org [accessed March 20, 2020]).
  23. ↑ Wolfgang Malzer, Daniel Grötzsch, Richard Gnewkow, Christopher Schlesiger, Fabian Kowalewski: A laboratory spectrometer for high throughput X-ray emission spectroscopy in catalysis research . In: Review of Scientific Instruments . tape 89 , no. November 11 , 2018, ISSN  0034-6748 , p. 113111 , doi : 10.1063 / 1.5035171 ( scitation.org [accessed March 20, 2020]).
  24. ↑ ERC Synergy Grant for Serena DeBeer and an international and interdisciplinary team. Retrieved March 20, 2020 .
  25. ↑ ERC 2019 Synergy Grants examples. October 10, 2019, accessed on March 20, 2020 .
  26. ↑ Serena DeBeer joins Chemical Science as an Associate Editor - Chemical Science Blog. Retrieved March 20, 2020 (American English).
  27. ↑ Dr. Serena Debeer - 2016 Inorganic Chemistry Le ... | ACS Network. Retrieved March 20, 2020 .
  28. ↑ SBIC - Serena DeBeer. Retrieved July 10, 2015 .
  29. ↑ Serena DeBeer: Spectroscopic Studies of N2 Reduction: From Biological to Heterogeneous Catalysis. Retrieved March 11, 2015 .
  30. ↑ Serena DeBeer. Retrieved March 20, 2020 .
  31. ^ Past Fellows. Retrieved March 20, 2020 .
personal data
SURNAME DeBeer, Serena
BRIEF DESCRIPTION American chemist
DATE OF BIRTH 1973