ChemphyschemPub Date : 2024-10-14DOI: 10.1002/cphc.202400720
Wenxi Zhang, Mengnan Qu, Aijun Du, Qiao Sun
{"title":"Electric-Field Controlled Switchable and Efficient Separation of Radioactive Xe/Kr on Borophene: A Theoretical Study.","authors":"Wenxi Zhang, Mengnan Qu, Aijun Du, Qiao Sun","doi":"10.1002/cphc.202400720","DOIUrl":"10.1002/cphc.202400720","url":null,"abstract":"<p><p>The efficient and reversible separation of radioactive Xe/Kr during spent fuel reprocessing is important and challenging for the rapid development of nuclear energy. In this study, we firstly report a strategy of applying an electric field on the solid adsorbent borophene to realize efficient and switchable Xe/Kr separation via a density functional theory (DFT) investigation. Based on the calculational results, the adsorption energies for Xe and Kr on borophene without an electric field are -0.25 eV and -0.18 eV, respectively, indicating that Xe and Kr can only form weak adsorption on borophene. However, by applying an electric field (0.006 a.u.) to the systems, the adsorption energies for Xe and Kr on borophene are -0.98 eV and -0.47 eV, respectively, which shows that the interaction between Xe and borophene has increased dramatically compared with that of Kr, so Xe can be separated from radioactive Xe/Kr mixtures. What's more, when the electric field is removed, desorption of Xe from the surface of borophene is exothermic without an energy barrier. The adsorbent is recyclable. In summary, this theoretical study provides novel information for experimental researches, the highly efficient Xe/Kr separation can be controlled by turning on/off the applied electric field.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400720"},"PeriodicalIF":4.6,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142459188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-14DOI: 10.1002/cphc.202400819
J A Laux, T Ohigashi, M R Bittermann, T Araki, H Yuzawa, F Rancan, A Vogt, E Rühl
{"title":"Scanning Transmission Soft X-Ray Microscopy Probes Topical Drug Delivery of Rapamycin Facilitated by Microneedles.","authors":"J A Laux, T Ohigashi, M R Bittermann, T Araki, H Yuzawa, F Rancan, A Vogt, E Rühl","doi":"10.1002/cphc.202400819","DOIUrl":"10.1002/cphc.202400819","url":null,"abstract":"<p><p>Scanning Transmission X-ray microscopy (STXM) is a sensitive and selective probe for the penetration of rapamycin which is topically applied to human skin ex vivo and is facilitated by skin treatment with microneedles puncturing the skin. Inner-shell excitation serves as a selective probe for detecting rapamycin by changes in optical density as well as linear combination modeling using reference spectra of the most abundant species. The results indicate that mechanical damage induced by microneedles allows this drug to accumulate in the stratum corneum without reaching the viable skin layers. This is unlike intact skin which shows no drug penetration at all and underscores the mechanical impact of microneedle skin treatment. These results are compared to drug penetration profiles of other drugs highlighting the importance of skin barriers. High spatial resolution studies also indicate that the lipophilic drug rapamycin is observed in corneocytes. Attempts in data evaluation are reported to probe rapamycin also in the lipid layers between the corneocytes, which was not accomplished before. These results are compared to recent results on rapamycin uptake in skin where barrier impairment was induced by pre-treatment with the enzyme trypsin and drug formulations leading to occlusion.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400819"},"PeriodicalIF":2.3,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142459195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-12DOI: 10.1002/cphc.202400406
Jeevanantham Sivaraj, Bosubabu Dasari, Prakash Subramani, Jayashree Pitchai, Sreekuttan M Unni, K Ramesha
{"title":"Nitrogen and Sulfur Doped Porous Carbon Sheet with Trace Amount of Iron as Efficient Polysulfide Conversion Catalyst for High Loading Lithium-Sulfur Batteries.","authors":"Jeevanantham Sivaraj, Bosubabu Dasari, Prakash Subramani, Jayashree Pitchai, Sreekuttan M Unni, K Ramesha","doi":"10.1002/cphc.202400406","DOIUrl":"10.1002/cphc.202400406","url":null,"abstract":"<p><p>The major challenges in enhancing the cycle life of lithium-sulfur (Li-S) batteries are polysulfide (PS) shuttling and sluggish reaction kinetics (S to Li<sub>2</sub>S, Li<sub>2</sub>S to S). To alleviate the above issues, the use of heteroatom-doped carbon as a cathode host matrix is a low-cost and efficient approach, as it works as a dual-functional framework for PS anchoring as well as an electrocatalyst for faster redox kinetics. Here, the dual role of heteroatom-doped carbon sheets (CS) in the chemisorption of Li<sub>2</sub>S<sub>6</sub> and catalysis of its faster conversion to Li<sub>2</sub>S is established. To substantiate the catalytic effect, composite cathodes were prepared by encapsulating sulfur in CS which is further blended with carbon nanotubes (CNTs) to form a free-standing cathode. The electrochemical performances of the three cathodes (S@Fe-N-CS-CNT, S@Fe-S-CS-CNT, and S@Fe-NS-CS-CNT) were evaluated by constructing Li-S cells. The S@Fe-NS-CS-CNT delivers a high initial discharge capacity of 1017 mAh g<sup>-1</sup> at 0.5 C rate and sustains a capacity of 751 mAh g<sup>-1</sup> after 260 cycles with a capacity retention of 73.8 %. Even at a high S loading (12 mg cm<sup>-2</sup>), it delivers an initial discharge capacity of 892 mAh g<sup>-1</sup> and retained 575 mAh g<sup>-1</sup> after 200 cycles.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400406"},"PeriodicalIF":2.3,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142459193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-11DOI: 10.1002/cphc.202400604
Zhiwei Gao, Wei Lai
{"title":"Structurally-Modulated Substrate of MXene for Surface-Enhanced Raman Scattering Sensing.","authors":"Zhiwei Gao, Wei Lai","doi":"10.1002/cphc.202400604","DOIUrl":"10.1002/cphc.202400604","url":null,"abstract":"<p><p>The distinctive structure of MXene offers exceptional electron transport properties, abundant surface chemistry, and robust mechanical attributes, thereby bestowing it with remarkable advantages and promising prospects in the realm of surface-enhanced Raman scattering (SERS). This review comprehensively outlines the evolution, synthesis methodologies, and characterization techniques employed for MXene-based SERS substrates. It delves into the intricacies of its SERS enhancement mechanism, substrate variants, and performance metrics, alongside showcasing its diverse applications spanning molecular detection, biosensing, and environmental monitoring. Furthermore, it endeavors to pinpoint the research bottlenecks and chart the future research trajectories for MXene-based SERS substrates.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400604"},"PeriodicalIF":2.3,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142399545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-09DOI: 10.1002/cphc.202400792
Ryo Sekiya, Takeharu Haino
{"title":"Assessment of Edge Modification of Nanographene.","authors":"Ryo Sekiya, Takeharu Haino","doi":"10.1002/cphc.202400792","DOIUrl":"https://doi.org/10.1002/cphc.202400792","url":null,"abstract":"<p><p>Carboxy groups on the edges of nanographene (NG) enable functionalization for realizing NG-organic hybrid materials. Therefore, assessment of the edge-functionalization of the electronic structures of NGs is valuable for the rational design of functional carbon materials. In this study, the structures of model NGs comprising 174 carbon atoms with armchair edges and various functional groups at the edges were computed. To achieve the greatest possible similarity between the computed structure and the real one, the carbon framework was designed based on experimental observations. The functional groups can be accessed via suitable chemical reactions. The computations predicted that although the conversion of carboxyl groups with electron-withdrawing/donating groups influences the orbital energies, the HOMO-LUMO (H-L) gap is not significantly affected, except in a few cases. Among the evaluated examples, π-extension had the greatest influence on the H-L gap. Interestingly, for the Pd2+-coordinated NG, the participation of the low-lying LUMO localized on Pd2+ in the surface-to-metal transitions seemingly narrowed the H-L gap, and a surface-to-ligand transition was observed.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400792"},"PeriodicalIF":2.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-09DOI: 10.1002/cphc.202400631
Sha-Sha Liu, Xin Wei, Yan Zheng, Shuai Liu, Dong-Hui Xu, Laicai Li, Ganglong Cui, Xiang-Yang Liu
{"title":"Conformational and Solvent Effects on the Photoinduced Electron Transfer Dynamics of a Zinc Phthalocyanine-Benzoperylenetriimide Conjugate: A Nonadiabatic Dynamics Simulation.","authors":"Sha-Sha Liu, Xin Wei, Yan Zheng, Shuai Liu, Dong-Hui Xu, Laicai Li, Ganglong Cui, Xiang-Yang Liu","doi":"10.1002/cphc.202400631","DOIUrl":"10.1002/cphc.202400631","url":null,"abstract":"<p><p>Herein, we employed a combination of static electronic structure calculations and nonadiabatic dynamics simulations at linear-response time dependent density functional theory (LR-TDDFT) level with the optimally tuned range-separated hybrid (OT-RSH) functional to explore the ultrafast photoinduced dynamics of a zinc phthalocyanine-benzoperylenetriimide (ZnPc-BPTI) conjugate. Due to the flexibility of the linker, we identified two major conformations: the stacked conformation (ZnPc-BPTI-1) and the extended conformation (ZnPc-BPTI-2). Since the charge transfer states are much lower than the lowest local excitation in ZnPc-BPTI-1, which is contrary to ZnPc-BPTI-2, the ultrafast electron transfer (~3.6 ps) is only observed in the nonadiabatic simulations of ZnPc-BPTI-1 upon local excitation around the absorption maximum of ZnPc. However, when considering the solvent effects in benzonitrile: the lowest S<sub>1</sub> states are both charge transfer states from ZnPc to BPTI for different conformers. Subsequent nonadiabatic dynamics simulations indicate that both conformers experience ultrafast electron transfer in benzonitrile with two time constants of 90 [100] fs and 1.40 [1.43] ps. Our present work not only agrees well with previous experimental study, but also points out the important role of conformational changes and solvent effects in regulating the photodynamics of organic donor-acceptor conjugates.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400631"},"PeriodicalIF":2.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-09DOI: 10.1002/cphc.202400731
Stuart J Elliott, Philip W Kuchel, Thomas R Eykyn
{"title":"Stretch-Induced Ordering of Prochiral Dimethyl Sulfoxide in Anisotropic Hydrogels Analysed by <sup>1</sup>H and <sup>2</sup>H Nuclear Magnetic Resonance.","authors":"Stuart J Elliott, Philip W Kuchel, Thomas R Eykyn","doi":"10.1002/cphc.202400731","DOIUrl":"10.1002/cphc.202400731","url":null,"abstract":"<p><p>Nuclear spins in small molecules dissolved in stretched hydrogels typically have population-averaged residual interactions. The nuclear magnetic resonance (NMR) spectra of these systems often show additional peaks and splittings compared with free solutions. Residual dipolar couplings (RDCs) and quadrupolar couplings (RQCs) are observed for guest <sup>1</sup>H and <sup>2</sup>H nuclear spins, respectively. Dimethyl sulfoxide (DMSO) is an exquisitely sensitive probe of such biologically relevant environments since it is prochiral and becomes effectively chiral when embedded in anisotropic gelatin-based hydrogels. Measured <sup>1</sup>H RDCs and <sup>2</sup>H RQCs were used to estimate bond order parameters over a wide range of stretching extents. At the largest extent of stretching, the <sup>2</sup>H splittings were -73.0 and -9.4 Hz, similar to those found for guest molecules in liquid crystals. Inhomogeneous line broadening of the <sup>2</sup>H resonances was related to the size of the RQC due to a spatial distribution of RQCs, which was revealed using a one-dimensional slice selective imaging experiment along the stretching direction. <sup>1</sup>H NMR spectra exhibited homogeneous line broadening, with resonance integrals that indicated concealed multiplet structure. Understanding molecular bond ordering in mechanically oriented environments provides a conceptual framework for investigating more complex systems including zeolites and those found in vivo.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400731"},"PeriodicalIF":2.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-09DOI: 10.1002/cphc.202400670
Aakash Rajpoot, Afaq Ahmad Khan, Indra Mohan, Siddhartha Sengupta, Ejaz Ahmad
{"title":"Stoichiometric-Ratio-Controlled Fe and Ni Non-Noble Metal Catalysts Supported on γ-Al<sub>2</sub>O<sub>3</sub> for Turquoise Hydrogen and Carbon Nanotubes Production.","authors":"Aakash Rajpoot, Afaq Ahmad Khan, Indra Mohan, Siddhartha Sengupta, Ejaz Ahmad","doi":"10.1002/cphc.202400670","DOIUrl":"10.1002/cphc.202400670","url":null,"abstract":"<p><p>Herein, we synthesized a series of catalysts comprising iron (Fe), and nickel (Ni) supported on γ-Al<sub>2</sub>O<sub>3</sub> nano-powder (Fe-Ni/γ-Al<sub>2</sub>O<sub>3</sub>) by controlling the stoichiometric ratio of the metals through the facile co-precipitation method. The ratio of Fe and Ni on the γ-Al<sub>2</sub>O<sub>3</sub> support varied from 0 to 70 weight percent (wt %). The freshly prepared catalysts phase, structure, and crystallinity exhibited variability as the Fe and Ni stoichiometric ratios were altered. The catalyst demonstrated effective performance in methane cracking, producing turquoise hydrogen and carbon nanotubes (CNTs) using a temperature-programmed reactor coupled with mass spectrometry. It was observed that the Fe3Ni4 catalyst, comprising 30 % Fe and 40 % Ni, exhibited a maximum methane conversion rate of 85 % and a hydrogen yield of 72.55 %. Moreover, the values of turnover frequency (2.38 min<sup>-1</sup>) indicated that the Fe3Ni4 had a better production rate and was consistent with the conversion process throughout the reaction. The structural attributes of the spent catalysts were examined, revealing variations in the lateral length, uniformity, and diameters (~33 to 56 nm) of the produced Carbon Nanotubes (CNTs) when transitioning from catalyst Fe0Ni7 to Fe7Ni0. The investigation underscored the significance of metal stoichiometrically controlled catalysts and their catalytic efficacy in methane cracking applications.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400670"},"PeriodicalIF":2.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-09DOI: 10.1002/cphc.202400517
Benjoe Rey B Visayas, Shyam K Pahari, Tulsi M Poudel, James A Golen, Patrick J Cappillino, Maricris L Mayes
{"title":"Designing Alkylammonium Cations for Enhanced Solubility of Anionic Active Materials in Redox Flow Batteries: The Role of Bulk and Chain Length.","authors":"Benjoe Rey B Visayas, Shyam K Pahari, Tulsi M Poudel, James A Golen, Patrick J Cappillino, Maricris L Mayes","doi":"10.1002/cphc.202400517","DOIUrl":"10.1002/cphc.202400517","url":null,"abstract":"<p><p>Advancing grid-scale energy storage technologies is crucial for realizing a fully renewable energy landscape, with non-aqueous redox flow batteries (NRFBs) presenting a promising solution. One of the current challenges in NRFBs stems from the low energy density of redox active materials, primarily due to their limited solubility in non-aqueous solvents. Herein, this study explores the solubility of vanadium(IV/V) bis-hydroxyiminodiacetate (VBH) crystals in acetonitrile, aiming to use them as anionic catholytes in NRFBs. We focused on enhancing VBH solubility by modifying the structure of the alkylammonium cation. Employing periodic density functional theory and a solvation model, we calculated the dissolution free energy <math> <semantics><mrow><mo>(</mo> <mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mi>d</mi> <mi>i</mi> <mi>s</mi></mrow> <msup><mrow></mrow> <mo>*</mo></msup> </msubsup> </mrow> <annotation>${({rm Delta }{G}_{dis}^{^{ast}}}$</annotation> </semantics> </math> ), which includes sublimation ( <math> <semantics><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mi>s</mi> <mi>u</mi> <mi>b</mi></mrow> <msup><mrow></mrow> <mo>*</mo></msup> </msubsup> </mrow> <annotation>${{rm Delta }{G}_{sub}^{^{ast}}}$</annotation> </semantics> </math> ) and solvation ( <math> <semantics><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mi>s</mi> <mi>o</mi> <mi>l</mi></mrow> <msup><mrow></mrow> <mo>*</mo></msup> </msubsup> </mrow> <annotation>${{rm Delta }{G}_{sol}^{^{ast}}}$</annotation> </semantics> </math> ) energies. Our results indicate that neither elongating straight-chain alkyl groups beyond a tetrabutylammonium baseline nor introducing bulky substituents at the nitrogen center significantly enhances solubility. However, the introduction of carbon spacers combined with terminal bulky substituents markedly improves solubility by favorably altering both <math> <semantics><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mi>s</mi> <mi>u</mi> <mi>b</mi></mrow> <msup><mrow></mrow> <mo>*</mo></msup> </msubsup> </mrow> <annotation>${{rm Delta }{G}_{sub}^{^{ast}}}$</annotation> </semantics> </math> and <math> <semantics><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mi>s</mi> <mi>o</mi> <mi>l</mi></mrow> <msup><mrow></mrow> <mo>*</mo></msup> </msubsup> </mrow> <annotation>${{rm Delta }{G}_{sol}^{^{ast}}}$</annotation> </semantics> </math> . These findings underline the nuanced impact of cation structure on solubility and suggest a viable approach to optimize VBH-based anionic catholytes. This advancement promises to enhance NRFB efficiency and sustainability, marking a significant step forward in energy storage technology.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400517"},"PeriodicalIF":2.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ChemphyschemPub Date : 2024-10-09DOI: 10.1002/cphc.202400453
Lisa Köhler, Florian Trunk, Valentin Rohr, Tobias Fischer, Wolfgang Gärtner, Josef Wachtveitl, Jörg Matysik, Chavdar Slavov, Chen Song
{"title":"Rotameric Heterogeneity of Conserved Tryptophan Is Responsible for Reduced Photochemical Quantum Yield in Cyanobacteriochrome Slr1393g3.","authors":"Lisa Köhler, Florian Trunk, Valentin Rohr, Tobias Fischer, Wolfgang Gärtner, Josef Wachtveitl, Jörg Matysik, Chavdar Slavov, Chen Song","doi":"10.1002/cphc.202400453","DOIUrl":"10.1002/cphc.202400453","url":null,"abstract":"<p><p>The red/green cyanobacteriochrome (CBCR) slr1393g3 exhibits a quantum yield of only 8 % for its forward photoconversion, significantly lower than other species from the same CBCR subfamily. The cause for this reduced photoconversion is not yet clear, although in the related NpR6012g4 dark-state structural heterogeneity of a paramount Trp residue has been proposed to cause the formation of nonproductive subpopulation. However, there is no such information on the equivalent residue in slr1393g3, W496. Here we use solid-state NMR to explore all possible sidechain rotamers of this Trp residue and their local interactions at the atomic level. The indole nitrogen (Nϵ1) is used as an NMR probe, achieved by site-specific <sup>15</sup>N-indole labeling of a quadruply Trp-deleted variant and trehalose vitrification technique. The data reveal a set of seven indole rotamers of W496 with four distinct environments for the Nϵ1-H group. Only a minority population of 20 % is found to retain the π-stacking and hydrogen-bonding interactions with the chromophore in the dark state that has been assigned to account for complete forward photoconversion. Our results demonstrate the direct role of W496 in modulating the forward quantum yield of slr1393g3 via rearrangement of its sidechain rotameric conformations.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400453"},"PeriodicalIF":2.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}