ACS Omega最新文献

{"title":"Conformational Flexibility of D1-Glu189: A Crucial Determinant in Substrate Water Selection, Positioning, and Stabilization within the Oxygen-Evolving Complex of Photosystem II","authors":"Hiroshi Isobe*,&nbsp;Takayoshi Suzuki,&nbsp;Michihiro Suga,&nbsp;Jian-Ren Shen and Kizashi Yamaguchi,&nbsp;","doi":"10.1021/acsomega.4c0998110.1021/acsomega.4c09981","DOIUrl":"https://doi.org/10.1021/acsomega.4c09981https://doi.org/10.1021/acsomega.4c09981","url":null,"abstract":"<p >Photosynthetic water oxidation is a vital process responsible for producing dioxygen and supplying the energy necessary to sustain life on Earth. This fundamental reaction is catalyzed by the oxygen-evolving complex (OEC) of photosystem II, which houses the Mn₄CaO₅ cluster as its catalytic core. In this study, we specifically focus on the D1-Glu189 amino acid residue, which serves as a direct ligand to the Mn₄CaO₅ cluster. Our primary goal is to explore, using density functional theory (DFT), how the conformational flexibility of the D1-Glu189 side chain influences crucial catalytic processes, particularly the selection, positioning, and stabilization of a substrate water molecule within the OEC. Our investigation is based on a hypothesis put forth by Li et al. (<i>Nature</i>, <b>2024</b>, <i>626</i>, 670), which suggests that during the transition from the S₂ to S₃ state, a specific water molecule temporarily coordinating with the Ca ion, referred to as O6*, may exist as a hydroxide ion (OH^–). Our results demonstrate a key mechanism by which the detachment of the D1-Glu189 carboxylate group from its coordination with the Ca ion allows the creation of a specialized microenvironment within the OEC that enables the selective attraction of O6* in its deprotonated form (OH^–) and stabilizes it at the catalytic metal (Mn_D) site. Our findings indicate that D1-Glu189 is not only a structural ligand for the Ca ion but may also play an active and dynamic role in the catalytic process, positioning O6* optimally for its subsequent participation in the oxidation sequence during the water-splitting cycle.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"50041–50048 50041–50048"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsomega.4c09981","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142842687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Celebrating 50 Years of Surface Enhanced Spectroscopy","authors":"Alexandre G. Brolo*,&nbsp; and ,&nbsp;Nathan C. Lindquist*,&nbsp;","doi":"10.1021/acsomega.4c1007110.1021/acsomega.4c10071","DOIUrl":"https://doi.org/10.1021/acsomega.4c10071https://doi.org/10.1021/acsomega.4c10071","url":null,"abstract":"","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"48867–48869 48867–48869"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsomega.4c10071","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142842682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"C-H Functionalization of Imidazo[1,5-<i>a</i>]pyridines: A Metal-Free Approach for Methylene Insertion to Access C(sp²)-C(sp³)-H-C(sp²) Bond Formation.","authors":"Shivangani Mahajan, Sanghapal D Sawant","doi":"10.1021/acsomega.4c03823","DOIUrl":"10.1021/acsomega.4c03823","url":null,"abstract":"<p><p>Formaldehyde has been used as a solvent and a source of carbon to insert a methylene group for bridging two imidazo[1,5-<i>a</i>]pyridine molecules without using any metal catalysis. This strategy has been extended on other alkyl-, aryl-, and heteroaryl aldehydes as well. This C(sp²)-C(sp³)-H-C(sp²) bond forming reaction proceeds via C(sp²)H functionalization of imidazo[1,5-<i>a</i>]pyridine and was applied on a wide range of substrates offering moderate to good yields of methylene-bridged/inserted bis-imidazo[1,5-<i>a</i>]pyridines. Most importantly, as an application, the bis-heteroarene product has been demonstrated as a ligand. The ligand-like behavior of bis-imidazo[1,5-<i>a</i>]pyridines has been demonstrated as an extension of current methodology. This reaction works well at the gram scale level.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"49071-49080"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11656365/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142875328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strategically Designed Ternary Nanohybrids of Titanate Nanosheet and Polydopamine-Coated Carbon Nanotubes for Highly Efficient Enrichment of Uranium(VI).","authors":"Zhiyang Jiang, Yuzhi Zhou, Wenshuo Wang, Zheng Yin, Mingze Zhao, Lei Yu, Sijie Ren, Han Xiao, Yanfang Ma","doi":"10.1021/acsomega.4c05253","DOIUrl":"10.1021/acsomega.4c05253","url":null,"abstract":"<p><p>A strategically designed ternary nanohybrid (TNS-PDA/CNT), consisting of titanate nanosheet (TNS) and polydopamine-modified multiwalled carbon nanotube (PDA/CNT composite), was synthesized by the facile hydrothermal method and wet impregnation method for removal of U(VI) from aqueous solution and were characterized by transmission electron microscopy (TEM), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), Raman spectroscopy, Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS). TNSs were introduced into the PDA/CNT composite, which effectively averted the agglomeration of the CNT and further exposed more adsorption sites. PDA thin layer exposing more active sites was conducive to enhance adsorption capacity and kinetic. The adsorption process was largely influenced by pH values and weakly affected by ionic strength, indicating that the adsorption process was controlled by inner-sphere surface complexes because of TNS-PDA/CNT with multiple functional groups, including imine, catechol, amine, and hydroxyl groups. The isotherm data could be well described by the Langmuir model, and the monolayer maximum adsorption was determined to be 309.60 mg/g at pH = 5.0 and temperature = 45 °C. Thermodynamic parameters (Δ<i>G</i>° < 0, Δ<i>S</i>° > 0, and Δ<i>H</i>° < 0) showed that the nature of adsorption was endothermic and spontaneous. By XRD, FT-IR, and XPS analyses, the adsorption mechanism mainly involved surface complexation and ion exchange. In summary, the TNS-PDA/CNT materials are fully qualified as a satisfactory adsorbent for the purification and recovery of U(VI) from wastewater.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"49108-49120"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11656379/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142875443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"C–H Functionalization of Imidazo[1,5-a]pyridines: A Metal-Free Approach for Methylene Insertion to Access C(sp2)–C(sp3)–H–C(sp2) Bond Formation","authors":"Shivangani Mahajan,&nbsp; and ,&nbsp;Sanghapal D. Sawant*,&nbsp;","doi":"10.1021/acsomega.4c0382310.1021/acsomega.4c03823","DOIUrl":"https://doi.org/10.1021/acsomega.4c03823https://doi.org/10.1021/acsomega.4c03823","url":null,"abstract":"<p >Formaldehyde has been used as a solvent and a source of carbon to insert a methylene group for bridging two imidazo[1,5-<i>a</i>]pyridine molecules without using any metal catalysis. This strategy has been extended on other alkyl-, aryl-, and heteroaryl aldehydes as well. This C(sp²)–C(sp³)–H–C(sp²) bond forming reaction proceeds via C(sp²)H functionalization of imidazo[1,5-<i>a</i>]pyridine and was applied on a wide range of substrates offering moderate to good yields of methylene-bridged/inserted bis-imidazo[1,5-<i>a</i>]pyridines. Most importantly, as an application, the bis-heteroarene product has been demonstrated as a ligand. The ligand-like behavior of bis-imidazo[1,5-<i>a</i>]pyridines has been demonstrated as an extension of current methodology. This reaction works well at the gram scale level.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"49071–49080 49071–49080"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsomega.4c03823","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142842439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of a Simple HPLC/UV Method for Assay and In Vitro Release of Glycosaminoglycan from Pharmaceutical Formulations","authors":"Gokselin Ozgen,&nbsp;Nahide Zeren Arda Ozturk,&nbsp;Gokce Turan,&nbsp;Merve Turk,&nbsp;Evren Homan Gokce,&nbsp;Ozgen Ozer,&nbsp;Hayriye Icin,&nbsp;Gonul Kayar,&nbsp;Enis Isik,&nbsp;Udaya Kumar Dude and Sakine Tuncay Tanrıverdi*,&nbsp;","doi":"10.1021/acsomega.4c0216110.1021/acsomega.4c02161","DOIUrl":"https://doi.org/10.1021/acsomega.4c02161https://doi.org/10.1021/acsomega.4c02161","url":null,"abstract":"<p >This study encompasses the validation of a simple, rapid, and sensitive HPLC/UV method developed in accordance with the guidelines set by ICH Q2(R2) for obtaining the active pharmaceutical ingredient from the glycosaminoglycan family in topical formulations. Previous methods reported for analyzing glycosaminoglycans in semisolid formulations are relatively complex and time-consuming, involving extraction, purification, and derivatization. This developed analytical method allows for straightforward extraction of the active pharmaceutical ingredient from the matrix, enabling the direct injection of samples. This method was performed and validated for the assay of the pharmaceutical gel and cream formulations to investigate the parameters of linearity (<i>r</i> = 0.9997 for the gel formulation and <i>r</i> = 0.9993 for the cream formulation), precision, accuracy, specificity, and robustness by HPLC/UV. Additionally, this method was used to determine the active ingredient in <i>in vitro</i> release studies. <i>In vitro</i> similarity correlation against commercial products was performed according to the Mann–Whitney <i>U</i> statistical test. The similarity results were 96.5–102.7% for the gel formulation and 98.0–106.0% for the cream formulation, which remained within the limits (75–133.33%) according to USP 1724. This proved that <i>in vitro</i> release profiles for both formulations were like those of the commercial product. In light of the research findings, we believe that the HPLC/UV analysis presented can be further enhanced in the future for determining the levels of active ingredients in various pharmaceutical formulations or for monitoring the levels of glycosaminoglycans in biological matrixes.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"49023–49031 49023–49031"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsomega.4c02161","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142842013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ellagic Acid Induces DNA Damage and Apoptosis in Cancer Stem-like Cells and Overcomes Cisplatin Resistance","authors":"Tanima Mandal,&nbsp;Devendra Shukla,&nbsp;Subhamoy Pattanayak,&nbsp;Raju Barman,&nbsp;Rahail Ashraf,&nbsp;Amit Kumar Dixit,&nbsp;Sanjay Kumar,&nbsp;Deepak Kumar and Amit Kumar Srivastava*,&nbsp;","doi":"10.1021/acsomega.3c0881910.1021/acsomega.3c08819","DOIUrl":"https://doi.org/10.1021/acsomega.3c08819https://doi.org/10.1021/acsomega.3c08819","url":null,"abstract":"<p >Cancer stem cells (CSCs) are responsible for chemoresistance and tumor relapse in many solid malignancies, including lung and ovarian cancer. Ellagic acid (EA), a natural polyphenol, exhibits anticancer effects on various human malignancies. However, its impact and mechanism of action on cancer stem-like cells (CSLCs) are only partially understood. In this study, we evaluated the therapeutic potential and underlying molecular mechanism of EA isolated from tropical mango against CSLCs. Herein, we observed that EA treatment reduces the stem-like phenotypes in cancer cells, thereby lowering the cell survival and self-renewal potential of ovarian and lung CSLCs. Additionally, EA treatment limits the populations of lung and ovarian CSLCs characterized by CD133⁺ and CD44⁺CD117⁺, respectively. A mechanistic investigation showed that EA treatment induces ROS generation by altering mitochondrial dynamics, causing changes in the levels of Drp1 and Mfn2, which lead to an increased level of accumulation of DNA damage and eventually trigger apoptosis in CSLCs. Moreover, pretreatment with EA sensitizes CSLCs to cisplatin treatment by enhancing DNA damage accumulation and impairing the DNA repair ability of the CSLCs. Furthermore, EA pretreatment significantly reduces cisplatin-induced mutation frequency and improves drug retention in CSLCs, potentially suppressing the development of acquired drug resistance. Taken together, our results demonstrate an unreported finding that EA inhibits CSLCs by targeting mitochondrial function and triggering apoptosis. Thus, EA can be used either alone or in combination with other chemotherepeutic drugs for the management of cancer.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"48988–49000 48988–49000"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsomega.3c08819","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142849930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights into Rock Wettability Influencing Factors: A Review","authors":"Xiao Deng,&nbsp;Ahmed Bashir,&nbsp;Muhammad Shahzad Kamal*,&nbsp;Arshad Raza,&nbsp;Shirish Patil,&nbsp;Xianmin Zhou,&nbsp;Mohamed Mahmoud and Syed Muhammad Shakil Hussain*,&nbsp;","doi":"10.1021/acsomega.4c0738710.1021/acsomega.4c07387","DOIUrl":"https://doi.org/10.1021/acsomega.4c07387https://doi.org/10.1021/acsomega.4c07387","url":null,"abstract":"<p >Wetting characteristics of a hydrocarbon reservoir are generally quantified for cost-effective field development. The wetting process of rock by oil is a complex process involving reactions among compounds (rock, oil, and brine), the impact of environmental conditions (temperature, pressure, etc.), and treatment history (coring, transportation, etc.). There has not been much attention given to understanding the mechanisms causing different rock wetting states to quantify rock’s wettability. This work aims to provide an in-depth insight into rock wettability influencing factors including CO₂ &amp; H₂. In addition, advanced computational approaches such as molecular dynamics simulation, computational fluid dynamics, and machine learning for wettability have also been reviewed to govern the undiscovered interactions and mechanisms of this complex process. The key observation is that the polarity of organic components (asphaltenes and long-chain acids) determines the oil wetness in crude oil. In addition, acidic polar organics dominate oil-wetting in carbonate rocks; basic polar organics are key in sandstone. Also, environmental factors such as water films, brine salinity, and pH influence wettability significantly.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"48899–48917 48899–48917"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsomega.4c07387","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142849931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear Optical Response of Tetrel-Modified Tetraphenyl-Adamantane Clusters","authors":"Ferdinand Ziese*,&nbsp; and ,&nbsp;Simone Sanna*,&nbsp;","doi":"10.1021/acsomega.4c0854110.1021/acsomega.4c08541","DOIUrl":"https://doi.org/10.1021/acsomega.4c08541https://doi.org/10.1021/acsomega.4c08541","url":null,"abstract":"<p >The second harmonic generation (SHG) properties of adamantane-based tetraphenyl clusters are predicted from first principles and analyzed on the basis of the involved electronic transitions. In particular, the effect of a tetrel substitution in the cluster core on the nonlinear optical response is investigated. Electronic transitions spatially localized at the substituents are found to be responsible for the optical nonlinearities. The intensity of the SHG signal grows with the atomic number of the considered tetrel. As the substitution does not distort the cluster core or substantially alter its symmetry, the enhanced SHG intensity is traced to a higher electron density at the substituents. The latter results in a larger spatial overlap of the states involved in the electronic transitions, which increases their probability. The presented results provide a theoretical foundation for the design of tailored nonlinear optical sources.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"49816–49824 49816–49824"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsomega.4c08541","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142850043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conformational Flexibility of D1-Glu189: A Crucial Determinant in Substrate Water Selection, Positioning, and Stabilization within the Oxygen-Evolving Complex of Photosystem II.","authors":"Hiroshi Isobe, Takayoshi Suzuki, Michihiro Suga, Jian-Ren Shen, Kizashi Yamaguchi","doi":"10.1021/acsomega.4c09981","DOIUrl":"10.1021/acsomega.4c09981","url":null,"abstract":"<p><p>Photosynthetic water oxidation is a vital process responsible for producing dioxygen and supplying the energy necessary to sustain life on Earth. This fundamental reaction is catalyzed by the oxygen-evolving complex (OEC) of photosystem II, which houses the Mn₄CaO₅ cluster as its catalytic core. In this study, we specifically focus on the D1-Glu189 amino acid residue, which serves as a direct ligand to the Mn₄CaO₅ cluster. Our primary goal is to explore, using density functional theory (DFT), how the conformational flexibility of the D1-Glu189 side chain influences crucial catalytic processes, particularly the selection, positioning, and stabilization of a substrate water molecule within the OEC. Our investigation is based on a hypothesis put forth by Li et al. (<i>Nature</i>, <b>2024</b>, <i>626</i>, 670), which suggests that during the transition from the S₂ to S₃ state, a specific water molecule temporarily coordinating with the Ca ion, referred to as O6*, may exist as a hydroxide ion (OH^-). Our results demonstrate a key mechanism by which the detachment of the D1-Glu189 carboxylate group from its coordination with the Ca ion allows the creation of a specialized microenvironment within the OEC that enables the selective attraction of O6* in its deprotonated form (OH^-) and stabilizes it at the catalytic metal (Mn_D) site. Our findings indicate that D1-Glu189 is not only a structural ligand for the Ca ion but may also play an active and dynamic role in the catalytic process, positioning O6* optimally for its subsequent participation in the oxidation sequence during the water-splitting cycle.</p>","PeriodicalId":22,"journal":{"name":"ACS Omega","volume":"9 50","pages":"50041-50048"},"PeriodicalIF":3.7,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11656237/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142875336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}