scholarly journals Mapping the Deformability of Natural and Designed Cellulosomes in solution

Author(s):  
Jonathan Dorival ◽  
Sarah Moraïs ◽  
Aurore Labourel ◽  
Bartosz Rozycki ◽  
Pierre A Cazade ◽  
...  

Abstract Background : Natural cellulosome multi-enzyme complexes, their components, and engineered ‘designer cellulosomes’ (DCs) promise an efficient means of breaking down cellulosic substrates into valuable biofuel products. Their broad uptake in biotechnology relies on boosting proximity-based synergy among the resident enzymes but the modular architecture challenges structure determination and rational design.Results: We used small angle X-ray scattering combined with molecular modeling to study the solution structure of cellulosomal components. These include three dockerin-bearing cellulases with distinct substrate specificities, original scaffoldins from the human gut bacterium Ruminococcus champanellensis (ScaA, ScaH and ScaK) and a trivalent cohesin-bearing designer scaffoldin (Scaf20L), followed by cellulosomal complexes comprising these components, and the nonavalent fully loaded Clostridium thermocellum CipA in complex with Cel8A from the same bacterium. The size analysis of Rg and Dmax values deduced from the scattering curves and corresponding molecular models highlight their variable aspects, depending on composition, size and spatial organization of the objects in solution.Conclusion: Our data quantifies variability of form and compactness of cellulosomal components in water and confirms that this native plasticity may well be related to speciation with respect to the substrate that is targeted. By showing that scaffoldins or components display enhanced compactness compared to the free objects, we provide new routes to rationally enhance their stability and performance in their environment of action.

2013 ◽  
Vol 46 (5) ◽  
pp. 1508-1512 ◽  
Author(s):  
Byron Freelon ◽  
Kamlesh Suthar ◽  
Jan Ilavsky

Coupling small-angle X-ray scattering (SAXS) and ultra-small-angle X-ray scattering (USAXS) provides a powerful system of techniques for determining the structural organization of nanostructured materials that exhibit a wide range of characteristic length scales. A new facility that combines high-energy (HE) SAXS and USAXS has been developed at the Advanced Photon Source (APS). The application of X-rays across a range of energies, from 10 to 50 keV, offers opportunities to probe structural behavior at the nano- and microscale. An X-ray setup that can characterize both soft matter or hard matter and high-Zsamples in the solid or solution forms is described. Recent upgrades to the Sector 15ID beamline allow an extension of the X-ray energy range and improved beam intensity. The function and performance of the dedicated USAXS/HE-SAXS ChemMatCARS-APS facility is described.


2009 ◽  
Vol 131 (2) ◽  
pp. 502-508 ◽  
Author(s):  
Morten Christensen ◽  
Kristoffer Haldrup ◽  
Klaus Bechgaard ◽  
Robert Feidenhans’l ◽  
Qingyu Kong ◽  
...  

2021 ◽  
Author(s):  
Andrew McMahon ◽  
Rebecca Andrews ◽  
Sohail V Ghani ◽  
Thorben Cordes ◽  
Achillefs N Kapanidis ◽  
...  

Many viruses form highly pleomorphic particles; in influenza, these particles range from spheres of ~ 100 nm in diameter to filaments of several microns in length. Virion structure is of interest, not only in the context of virus assembly, but also because pleomorphic variations may correlate with infectivity and pathogenicity. Detailed images of virus morphology often rely on electron microscopy, which is generally low throughput and limited in molecular identification. We have used fluorescence super-resolution microscopy combined with a rapid automated analysis pipeline to image many thousands of individual influenza virions, gaining information on their size, morphology and the distribution of membrane-embedded and internal proteins. This large-scale analysis revealed that influenza particles can be reliably characterised by length, that no spatial frequency patterning of the surface glycoproteins occurs, and that RNPs are preferentially located towards filament ends within Archetti bodies. Our analysis pipeline is versatile and can be adapted for use on multiple other pathogens, as demonstrated by its application for the size analysis of SARS-CoV-2. The ability to gain nanoscale structural information from many thousands of viruses in just a single experiment is valuable for the study of virus assembly mechanisms, host cell interactions and viral immunology, and should be able to contribute to the development of viral vaccines, anti-viral strategies and diagnostics.


2006 ◽  
Vol 62 (a1) ◽  
pp. s264-s264
Author(s):  
K. Shiozawa ◽  
P. Konarev ◽  
C. Neufeld ◽  
W. A. Stanley ◽  
M. Wilmanns ◽  
...  

2014 ◽  
Vol 70 (a1) ◽  
pp. C1173-C1173
Author(s):  
Kamila Wiaderek ◽  
Olaf Borkiewicz ◽  
Nathalie Pereira ◽  
Jan Ilavsky ◽  
Glenn Amatucci ◽  
...  

Batteries are complex multicomponent devices wherein mesoscale phenomena–the nanoscale structure and chemistry of different components, and interactions thereof–drive functionality and performance. For example, electron/ion transport within the composite electrodes relies on bi-continuous nanostructuring to form electrically and ionicly conductive paths. Electrochemical conversion of different salts of a given metal yields a common and ostensibly identical product: the zero valent metal. For example, maximal lithiation of iron-based electrodes produces metallic iron nanoparticles for oxide, fluoride, and oxyfluoride electrodes alike. Accordingly, these provide an opportunity to explore the coupling of nanostructure development and anion chemistry, and correlate these with electrochemical performance. We combine synchrotron-based small angle X-ray scattering (SAXS) and pair distribution function (PDF) measurements to probe metallic iron formed by electrochemical conversion of different iron compounds across multiple length-scales and decouple the influence of anion chemistry and reaction temperature on the atomic structure and nanoscale morphology.


2021 ◽  
Author(s):  
Francesco Bizzotto ◽  
Jonathan Quinson ◽  
Johanna Schröder ◽  
Alessandro Zana ◽  
Matthias Arenz

Supported Ir oxide catalysts obtained from surfactant-free colloidal Ir nanoparticles (NPs) synthesized in alkaline methanol (MeOH), ethanol (EtOH), and ethylene glycol (EG) are investigated and compared. The comparison of independent techniques such as transition electron microscopy (TEM), small angle X-ray scattering (SAXS), and electrochemistry allows shedding light on the parameters that affect the dispersion of the active phase as well as the catalytic activity. The colloidal dispersions obtained are suitable to develop supported catalysts with little NP agglomeration on a carbon support leading to highly active catalysts with more than 400 A g<sup>-1</sup><sub>Ir</sub> reached at 1.5 V<sub>RHE</sub> for the OER. While the more common surfactant-free alkaline EG synthesis requires flocculation and re-dispersion leading to Ir loss, the main difference between methanol and ethanol as solvent is related to the dispersibility of the support material. The choice of the suitable monoalcohol determines the maximum achieved Ir loading on the support without detrimental particle agglomeration. This simple consideration on catalyst design can readily lead to significantly improved catalysts.


2005 ◽  
Vol 353 (1) ◽  
pp. 155-173 ◽  
Author(s):  
Zhe Sun ◽  
Adel Almogren ◽  
Patricia B. Furtado ◽  
Badrun Chowdhury ◽  
Michael A. Kerr ◽  
...  

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