I18-Microfocus Spectroscopy
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N. P.
Edwards
,
P. L.
Manning
,
U.
Bergmann
,
P. L.
Larson
,
B. E.
Van Dongen
,
W. I.
Sellers
,
S. M.
Webb
,
D.
Sokaras
,
R.
Alonso-Mori
,
K.
Ignatyev
,
H. E.
Barden
,
A.
Van Veelen
,
J.
Anne
,
V. M.
Egerton
,
R. A.
Wogelius
Diamond Proposal Number(s):
[8597]
Open Access
Abstract: Large-scale Synchrotron Rapid Scanning X-ray Fluorescence (SRS-XRF) elemental mapping and X-ray absorption spectroscopy are applied here to fossil leaf material from the ∼50 Mya Green River Formation (USA) in order to improve our understanding of the chemistry of fossilized plant remains. SRS-XRF of fossilized animals has previously shown that bioaccumulated trace metals and sulfur compounds may be preserved in their original distributions and these elements can also act as biomarkers for specific biosynthetic pathways. Similar spatially resolved chemical data for fossilized plants is sparsely represented in the literature despite the multitude of other chemical studies performed. Here, synchrotron data from multiple specimens consistently show that fossil leaves possess chemical inventories consisting of organometallic and organosulfur compounds that: (1) map discretely within the fossils, (2) resolve fine scale biological structures, and (3) are distinct from embedding sedimentary matrices. Additionally, the chemical distributions in fossil leaves are directly comparable to those of extant leaves. This evidence strongly suggests that a significant fraction of the chemical inventory of the examined fossil leaf material is derived from the living organisms and that original bioaccumulated elements have been preserved in situ for 50 million years. Chemical information of this kind has so far been unknown for fossilized plants and could for the first time allow the metallome of extinct flora to be studied.
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Apr 2014
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I18-Microfocus Spectroscopy
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J.
Anne
,
N. P.
Edwards
,
R. A.
Wogelius
,
A. R.
Tumarkin-Deratzian
,
W. I.
Sellers
,
A.
Van Veelen
,
U.
Bergmann
,
D.
Sokaras
,
R.
Alonso-Mori
,
K.
Ignatyev
,
V. M.
Egerton
,
P. L.
Manning
Open Access
Abstract: Current understanding of bone healing and remodelling strategies in vertebrates has traditionally relied on morphological observations through the histological analysis of thin sections. However, chemical analysis may also be used in such interpretations, as different elements are known to be absorbed and used by bone for different physiological purposes such as growth and healing. These chemical signatures are beyond the detection limit of most laboratory-based analytical techniques (e.g. scanning electron microscopy). However, synchrotron rapid scanningX-ray fluorescence (SRSXRF) is an elemental mapping technique that uniquely combines high sensitivity (ppm), excellent sample resolution (20100 µm) and the ability to scan large specimens (decimetre scale) approximately 3000 times faster than other mapping techniques. Here, we use SRSXRF combined with microfocus elemental mapping (220 µm) to determine the distribution and concentration of trace elements within pathological and normal bone of both extant and extinct archosaurs (Cathartes aura and Allosaurus fragilis). Results reveal discrete chemical inventories within different bone tissue types and preservation modes. Chemical inventories also revealed detail of histological features not observable in thin section, including fine structures within the interface between pathological and normal bone as well as woven texture within pathological tissue.
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Jul 2014
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I18-Microfocus Spectroscopy
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Diamond Proposal Number(s):
[8597]
Open Access
Abstract: Many exceptionally preserved fossils have long been thought the product of preservation by bacterial autolithification, based largely upon the presence of, micron-sized, spherical or elongate bodies on their surface. This has recently been challenged by studies of similar fossils which cite morphological and geochemical evidence that these structures could be fossilized melanosomes, melanin-containing organelles. We geochemically analysed a tadpole from the Oligocene Enspel Formation, Germany, which displays such spherical bodies on its surface. Pyrolysis gas chromatography mass spectroscopy (Py-GCMS) and Fourier transform infrared spectrometry (FTIR) indicate that the organic remains of the tadpole are original and are not the result of external contamination, shown by the different chemical compositions of the fossil and its enclosing matrix. Py-GCMS also demonstrates the presence of bacterial and plant biomarkers in the matrix but not the tadpole, suggesting that the spherical bodies are unlikely to be bacterial, and also that such fossils do not develop their dark colour from incorporating plant material, as has been suggested. X-ray absorption spectroscopy (XAS) shows high levels of organically bound Zn(II) in the fossilized soft tissue, a metal known to chelate both eu- and pheomelanin. The zinc in the tadpole shows greater similarity to that bound in pheomelanized extant samples than to that in eumelanized ones. Though further geochemical analysis of both pure pheomelanin and bacterial samples is required to completely exclude a bacterial origin, these results are in line with a pheomelanic origin for the spherical bodies on the tadpole.
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Nov 2014
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I18-Microfocus Spectroscopy
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Victoria
Egerton
,
Roy A.
Wogelius
,
Mark A.
Norell
,
Nicholas
Edwards
,
William
Sellers
,
Uwe
Bergmann
,
Dimosthenis
Sokaras
,
Roberto
Alonso-Mori
,
Konstantin
Ignatyev
,
Arjen
Van Veelen
,
Jennifer
Anné
,
Bart
Van Dongen
,
Fabien
Knoll
,
Phillip
Manning
Diamond Proposal Number(s):
[8597, 9488]
Open Access
Abstract: The preservation of fossils reflects the interplay of inorganic and organic chemical processes, which should be clearly differentiated to make interpretations about the biology of extinct organisms. A new coliiformes bird (mouse bird) from the [similar]50 million year old Green River Formation (Wyoming, USA) has here been analysed using synchrotron X-ray fluorescence and environmental scanning electron microscopy with an attached X-ray energy dispersive system (ESEM-EDS). The concentration and distribution of 16 elements (Si, P, S, Cl, K, Ca, Ti, Mg, Fe, Ni, Cu, Zn, As, Br, Ba, Hg) has been mapped for individual points on the sample. S, Cu and Zn map distinctly within visibly preserved feathers and X-ray Absorption Spectroscopy (XAS) shows that S and Cu within the feathers are organically bound in a similar manner to modern feathers. The morphological preservation of the feathers, on both macro- and microscopic scales, is variable throughout the fossil and the differences in the lateral microfacies have resulted in a morphological preservation gradient. This study clearly differentiates endogenous organic remains from those representing exogenous overprinted geochemical precipitates and illustrates the chemical complexity of the overall taphonomic process.
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Jan 2015
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I18-Microfocus Spectroscopy
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Nicholas
Edwards
,
Arjen
Van Veelen
,
Jennifer
Anné
,
Phillip
Manning
,
Uwe
Bergmann
,
William
Sellers
,
Victoria
Egerton
,
Dimosthenis
Sokaras
,
Roberto
Alonso-Mori
,
Kazumasa
Wakamatsu
,
Shosuke
Ito
,
Roy A.
Wogelius
Diamond Proposal Number(s):
[11865, 12948]
Open Access
Abstract: Melanin is a critical component of biological systems, but the exact chemistry of melanin is still imprecisely known. This is partly due to melanin’s complex heterogeneous nature and partly because many studies use synthetic analogues and/or pigments extracted from their natural biological setting, which may display important differences from endogenous pigments. Here we demonstrate how synchrotron X-ray analyses can non-destructively characterise the elements associated with melanin pigment in situ within extant feathers. Elemental imaging shows that the distributions of Ca, Cu and Zn are almost exclusively controlled by melanin pigment distribution. X-ray absorption spectroscopy demonstrates that the atomic coordination of zinc and sulfur is different within eumelanised regions compared to pheomelanised regions. This not only impacts our fundamental understanding of pigmentation in extant organisms but also provides a significant contribution to the evidence-based colour palette available for reconstructing the appearance of fossil organisms.
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Sep 2016
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Iris D.
Young
,
Mohamed
Ibrahim
,
Ruchira
Chatterjee
,
Sheraz
Gul
,
Franklin D.
Fuller
,
Sergey
Koroidov
,
Aaron S.
Brewster
,
Rosalie
Tran
,
Roberto
Alonso-Mori
,
Thomas
Kroll
,
Tara
Michels-Clark
,
Hartawan
Laksmono
,
Raymond G.
Sierra
,
Claudiu A.
Stan
,
Rana
Hussein
,
Miao
Zhang
,
Lacey
Douthit
,
Markus
Kubin
,
Casper
De Lichtenberg
,
Long
Vo Pham
,
Håkan
Nilsson
,
Mun Hon
Cheah
,
Dmitriy
Shevela
,
Claudio
Saracini
,
Mackenzie A.
Bean
,
Ina
Seuffert
,
Dimosthenis
Sokaras
,
Tsu-Chien
Weng
,
Ernest
Pastor
,
Clemens
Weninger
,
Thomas
Fransson
,
Louise
Lassalle
,
Philipp
Bräuer
,
Pierre
Aller
,
Peter T.
Docker
,
Babak
Andi
,
Allen M.
Orville
,
James M.
Glownia
,
Silke
Nelson
,
Marcin
Sikorski
,
Diling
Zhu
,
Mark S.
Hunter
,
Thomas J.
Lane
,
Andy
Aquila
,
Jason E.
Koglin
,
Joseph
Robinson
,
Mengning
Liang
,
Sébastien
Boutet
,
Artem Y.
Lyubimov
,
Monarin
Uervirojnangkoorn
,
Nigel W.
Moriarty
,
Dorothee
Liebschner
,
Pavel V.
Afonine
,
David G.
Waterman
,
Gwyndaf
Evans
,
Philippe
Wernet
,
Holger
Dobbek
,
William I.
Weis
,
Axel T.
Brunger
,
Petrus H.
Zwart
,
Paul D.
Adams
,
Athina
Zouni
,
Johannes
Messinger
,
Uwe
Bergmann
,
Nicholas K.
Sauter
,
Jan
Kern
,
Vittal K.
Yachandra
,
Junko
Yano
Abstract: Light-induced oxidation of water by photosystem II (PS II) in plants, algae and cyanobacteria has generated most of the dioxygen in the atmosphere. PS II, a membrane-bound multi-subunit pigment protein complex, couples the one-electron photochemistry at the reaction centre with the four-electron redox chemistry of water oxidation at the Mn4CaO5 cluster in the oxygen-evolving complex (OEC). Under illumination, the OEC cycles through five intermediate S-states (S0 to S4)1, in which S1 is the dark-stable state and S3 is the last semi-stable state before O–O bond formation and O2 evolution2, 3. A detailed understanding of the O–O bond formation mechanism remains a challenge, and will require elucidation of both the structures of the OEC in the different S-states and the binding of the two substrate waters to the catalytic site4, 5, 6. Here we report the use of femtosecond pulses from an X-ray free electron laser (XFEL) to obtain damage-free, room temperature structures of dark-adapted (S1), two-flash illuminated (2F; S3-enriched), and ammonia-bound two-flash illuminated (2F-NH3; S3-enriched) PS II. Although the recent 1.95 Å resolution structure of PS II at cryogenic temperature using an XFEL7 provided a damage-free view of the S1 state, measurements at room temperature are required to study the structural landscape of proteins under functional conditions8, 9, and also for in situ advancement of the S-states. To investigate the water-binding site(s), ammonia, a water analogue, has been used as a marker, as it binds to the Mn4CaO5 cluster in the S2 and S3 states10. Since the ammonia-bound OEC is active, the ammonia-binding Mn site is not a substrate water site10, 11, 12, 13. This approach, together with a comparison of the native dark and 2F states, is used to discriminate between proposed O–O bond formation mechanisms.
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Nov 2016
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Franklin D
Fuller
,
Sheraz
Gul
,
Ruchira
Chatterjee
,
E. Sethe
Burgie
,
Iris D.
Young
,
Hugo
Lebrette
,
Vivek
Srinivas
,
Aaron
Brewster
,
Tara
Michels-Clark
,
Jonathan A
Clinger
,
Babak
Andi
,
Mohamed
Ibrahim
,
Ernest
Pastor
,
Casper
De Lichtenberg
,
Rana
Hussein
,
Christopher J
Pollock
,
Miao
Zhang
,
Claudiu A
Stan
,
Thomas
Kroll
,
Thomas
Fransson
,
Clemens
Weninger
,
Markus
Kubin
,
Pierre
Aller
,
Louise
Lassalle
,
Philipp
Braeuer
,
Mitchell D.
Miller
,
Muhamed
Amin
,
Sergey
Koroidov
,
Christian G.
Roessler
,
Marc
Allaire
,
Raymond G
Sierra
,
Peter T.
Docker
,
James M.
Glownia
,
Silke
Nelson
,
Jason E
Koglin
,
Diling
Zhu
,
Matthieu
Chollet
,
Sanghoon
Song
,
Henrik
Lemke
,
Mengning
Liang
,
Dimosthenis
Sokaras
,
Roberto
Alonso-Mori
,
Athina
Zouni
,
Johannes
Messinger
,
Uwe
Bergmann
,
Amie K.
Boal
,
J. Martin
Bollinger
,
Carsten
Krebs
,
Martin
Högbom
,
George N.
Phillips
,
Richard D.
Vierstra
,
Nicholas K
Sauter
,
Allen M.
Orville
,
Jan
Kern
,
Vittal K
Yachandra
,
Junko
Yano
Abstract: X-ray crystallography at X-ray free-electron laser sources is a powerful method for studying macromolecules at biologically relevant temperatures. Moreover, when combined with complementary techniques like X-ray emission spectroscopy, both global structures and chemical properties of metalloenzymes can be obtained concurrently, providing insights into the interplay between the protein structure and dynamics and the chemistry at an active site. The implementation of such a multimodal approach can be compromised by conflicting requirements to optimize each individual method. In particular, the method used for sample delivery greatly affects the data quality. We present here a robust way of delivering controlled sample amounts on demand using acoustic droplet ejection coupled with a conveyor belt drive that is optimized for crystallography and spectroscopy measurements of photochemical and chemical reactions over a wide range of time scales. Studies with photosystem II, the phytochrome photoreceptor, and ribonucleotide reductase R2 illustrate the power and versatility of this method.
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Feb 2017
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I18-Microfocus Spectroscopy
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Jennifer
Anne
,
Roya A.
Wogelius
,
Nicholas P.
Edwards
,
Arjen
Van Veelen
,
Michael
Buckley
,
William
Sellers
,
Uwe
Bergmann
,
Dimosthenis
Sokaras
,
Roberto
Alonso-Mori
,
Virginia L.
Harvey
,
Victoria M.
Egerton
,
Phillip L.
Manning
Diamond Proposal Number(s):
[9488]
Abstract: Trace element inventories are known to correlate with specific histological structures in bone, reflecting organismal physiology and life histories. By studying trace elements in fossilised bone, particularly in individuals with cyclic bone growth (alternating fast/slow bone deposition), we can improve our understanding of the physiology of extinct organisms. In this study we present the first direct comparison between optical histology (bone tissue identification) and synchrotron-based chemical mapping, quantification, and characterisation of trace elements (biochemistry) within cyclic growth tissues, in this case within bones of a cave hyaena (Crocuta crocuta spelaea). Results show distributions of zinc, an element strongly associated with active ossification and bone growth, correlating with (1) fast-growing tissue of zonal bone (cyclic growth) in an extinct hyaena and (2) secondary osteons (remodelling) in both extant and extinct hyaena. Concentrations and coordination chemistry of zinc within the fossil sample are comparable to those seen in extant bone suggesting that zinc is endogenous to the sample and that the chemistry of bone growth has been preserved for 40 ka. These results demonstrate that the study of trace elements as part of the histochemistry has wide utility for reconstructing growth, diet and other lifestyle factors in archaeological and fossil bone.
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Oct 2018
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Jan
Kern
,
Ruchira
Chatterjee
,
Iris D.
Young
,
Franklin D.
Fuller
,
Louise
Lassalle
,
Mohamed
Ibrahim
,
Sheraz
Gul
,
Thomas
Fransson
,
Aaron S.
Brewster
,
Roberto
Alonso-Mori
,
Rana
Hussein
,
Miao
Zhang
,
Lacey
Douthit
,
Casper
De Lichtenberg
,
Mun Hon
Cheah
,
Dmitry
Shevela
,
Julia
Wersig
,
Ina
Seuffert
,
Dimosthenis
Sokaras
,
Ernest
Pastor
,
Clemens
Weninger
,
Thomas
Kroll
,
Raymond G.
Sierra
,
Pierre
Aller
,
Agata
Butryn
,
Allen M.
Orville
,
Mengning
Liang
,
Alexander
Batyuk
,
Jason E.
Koglin
,
Sergio
Carbajo
,
Sébastien
Boutet
,
Nigel W.
Moriarty
,
James M.
Holton
,
Holger
Dobbek
,
Paul D.
Adams
,
Uwe
Bergmann
,
Nicholas K.
Sauter
,
Athina
Zouni
,
Johannes
Messinger
,
Junko
Yano
,
Vittal K.
Yachandra
Abstract: Inspired by the period-four oscillation in flash-induced oxygen evolution of photosystem II discovered by Joliot in 1969, Kok performed additional experiments and proposed a five-state kinetic model for photosynthetic oxygen evolution, known as Kok’s S-state clock or cycle1,2. The model comprises four (meta)stable intermediates (S0, S1, S2 and S3) and one transient S4 state, which precedes dioxygen formation occurring in a concerted reaction from two water-derived oxygens bound at an oxo-bridged tetra manganese calcium (Mn4CaO5) cluster in the oxygen-evolving complex3,4,5,6,7. This reaction is coupled to the two-step reduction and protonation of the mobile plastoquinone QB at the acceptor side of PSII. Here, using serial femtosecond X-ray crystallography and simultaneous X-ray emission spectroscopy with multi-flash visible laser excitation at room temperature, we visualize all (meta)stable states of Kok’s cycle as high-resolution structures (2.04–2.08 Å). In addition, we report structures of two transient states at 150 and 400 µs, revealing notable structural changes including the binding of one additional ‘water’, Ox, during the S2→S3 state transition. Our results suggest that one water ligand to calcium (W3) is directly involved in substrate delivery. The binding of the additional oxygen Ox in the S3 state between Ca and Mn1 supports O–O bond formation mechanisms involving O5 as one substrate, where Ox is either the other substrate oxygen or is perfectly positioned to refill the O5 position during O2 release. Thus, our results exclude peroxo-bond formation in the S3 state, and the nucleophilic attack of W3 onto W2 is unlikely.
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Nov 2018
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I18-Microfocus Spectroscopy
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Phillip L.
Manning
,
Nicholas P.
Edwards
,
Uwe
Bergmann
,
Jennifer
Anne
,
William
Sellers
,
Arjen
Van Veelen
,
Dimosthenis
Sokaras
,
Victoria M.
Egerton
,
Roberto
Alonso-Mori
,
Konstantin
Ignatyev
,
Bart E.
Van Dongen
,
Kazumasa
Wakamatsu
,
Shosuke
Ito
,
Fabien
Knoll
,
Roy A.
Wogelius
Diamond Proposal Number(s):
[12948, 11865, 9488, 8597, 7749]
Open Access
Abstract: Recent progress has been made in paleontology with respect to resolving pigmentation in fossil material. Morphological identification of fossilized melanosomes has been one approach, while a second methodology using chemical imaging and spectroscopy has also provided critical information particularly concerning eumelanin (black pigment) residue. In this work we develop the chemical imaging methodology to show that organosulfur-Zn complexes are indicators of pheomelanin (red pigment) in extant and fossil soft tissue and that the mapping of these residual biochemical compounds can be used to restore melanin pigment distribution in a 3 million year old extinct mammal species (Apodemus atavus). Synchotron Rapid Scanning X-ray Fluorescence imaging showed that the distributions of Zn and organic S are correlated within this fossil fur just as in pheomelanin-rich modern integument. Furthermore, Zn coordination chemistry within this fossil fur is closely comparable to that determined from pheomelanin-rich fur and hair standards. The non-destructive methods presented here provide a protocol for detecting residual pheomelanin in precious specimens.
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May 2019
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