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Chlorosomes from green photosynthetic bacteria are large photosynthetic antennae containing self-assembling aggregates of bacteriochlorophyll c, d, or e. The pigments within chlorosomes are organized in curved lamellar structures. Aggregates with similar optical properties can be prepared in vitro, both in polar as well as non-polar solvents. In order to gain insight into their structure we examined hexane-induced aggregates of purified bacteriochlorophyll c by X-ray scattering. The bacteriochlorophyll c aggregates exhibit scattering features that are virtually identical to those of native chlorosomes demonstrating that the self-assembly of these pigments is fully encoded in their chemical structure. Thus, the hexane-induced aggregates constitute an excellent model to study the effects of chemical structure on assembly. Using bacteriochlorophyllides transesterified with different alcohols we have established a linear relationship between the esterifying alcohol length and the lamellar spacing. The results provide a structural basis for lamellar spacing variability observed for native chlorosomes from different species. A plausible physiological role of this variability is discussed. The X-ray scattering also confirmed the assignments of peaks, which arise from the crystalline baseplate in the native chlorosomes.
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http://dx.doi.org/10.1007/s11120-010-9541-0 | DOI Listing |
Phys Chem Chem Phys
September 2025
Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, USA.
Charge carrier mobility is a key factor underlying the performance of conjugated polymers as conductive materials for flexible and lightweight electronics. Chemical doping is typically used to improve polymer conductivity by increasing the carrier density. However, doping consequently induces both morphological and electrostatic changes within the polymer that impact charge mobility, the extent to which remains unclear.
View Article and Find Full Text PDFJ Synchrotron Radiat
September 2025
NSLS II, Brookhaven National Laboratory, BNL Building 703, Upton, NY 11973, USA.
We have developed a new process for the production of ultra-precise variable line spacing (VLS) lamellar diffraction gratings through nanofabrication. The process enables the fabrication of full-size X-ray gratings with sub-nanometre accuracy in groove depth, an optimal land-to-groove ratio, and uniform groove depth across the entire grating area. We also established a method for evaluating VLS groove density variation using stitched Fizeau interferometry.
View Article and Find Full Text PDFJ Hazard Mater
September 2025
State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, PR China. Electronic address:
Molybdenum diselenide (MoSe) is promising for capturing heavy metal ions, due to its sandwich-like Se-Mo-Se layers. However, limited by the narrow interlayer spacing, the majority of Se atoms in MoSe are not effectively available to the hydrated metal ions. Herein, ethylenediamine (EDA) intercalated MoSe has been prepared not only to expose more binding sites than that of bulk MoSe, but also to overcome the limitations associated with the self-aggregation and inferior stability of 2D single layer.
View Article and Find Full Text PDFElectromagnetic wave absorption materials play an increasingly important role in modern society for military stealth technology and 5G smart era. Microcrystalline graphene oxide (MGO) absorption materials have prepared by chemical oxidation method using microcrystalline graphite as raw material. The lamellar structure, functional groups, defects, and microwave absorption properties of MGO have characterized by X-ray diffractometer (XRD), Raman Spectrometer (Raman), Fourier Transform Infrared Spectrometer (FT-IR), Atomic Force Microscope (AFM), and Vector Network Analyzer (VNA).
View Article and Find Full Text PDFACS Appl Mater Interfaces
July 2025
School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea.
Three-dimensionally ordered photonic colloids offer a unique opportunity to directly correlate internal nanoscale morphology with the macroscale optical response. Herein, we present pH-responsive poly(styrene--2-vinylpyridine) (PS--P2VP) colloids with stacked lamellar architecture that exhibit tunable structural color through controlled swelling dynamics. Cross-linking P2VP domains using 1,8-dibromooctane increases initial domain spacing, shifting color from violet to blue-green, while simultaneously restricting acid-induced swelling and red shift.
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