Faraday Discussions最新文献

Investigating the co-assembly of amphipathic peptides. 研究两亲肽的共组装。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-07-08 DOI: 10.1039/d5fd00036j

Zixuan Liu, Alberto Saiani, Aline F Miller

引用次数: 0

The detection efficiency of low-dose cryo-4D STEM for biogenic crystals in frozen-hydrated samples. 低剂量冷冻- 4d STEM对冷冻水合样品中生物源晶体的检测效率。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-30 DOI: 10.1039/d5fd00027k

Lothar Houben, Zohar Eyal, Dvir Gur

{"title":"The detection efficiency of low-dose cryo-4D STEM for biogenic crystals in frozen-hydrated samples.","authors":"Lothar Houben, Zohar Eyal, Dvir Gur","doi":"10.1039/d5fd00027k","DOIUrl":"https://doi.org/10.1039/d5fd00027k","url":null,"abstract":"Multimodal scanning transmission electron microscopy on vitrified frozen-hydrated specimens promises exceptional spatial resolution into the molecular mechanisms underlying the formation of organic crystals in both health and disease. Detection of crystalline volumes is essential for tracking and mapping nucleation and growth. We provide an analytical description of the low-dose detection limit in diffraction for a thin crystal embedded in a thick matrix, focusing on organic crystals and embedding matrices of low-Z elements such as vitrified ice. Numerical calculations refine our description by accounting for the effects of multiple scattering. Often underestimated, wide-angle tails associated with inelastic scattering play a crucial role for the detection of crystalline reflections in a thick ice matrix, common for cryo-electron microscopy. We show that guanine crystals as thin as a few nanometers can be detected with a fluence of just a few thousand electrons if the ice thickness is below one mean free path for inelastic scattering. The required fluence increases non-linearly with the embedding ice thickness, with a pronounced top-bottom effect regarding the location of the crystal in the sample. Energy-filtered recording significantly reduces the fluence needed for thicker samples. The low-dose simulations implemented here validate the analytical description while acknowledging its limitations due to abstraction from multiple scattering and beam spreading.","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144525533","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}

引用次数: 0

Advanced imaging techniques in biomineralisation research. 生物矿化研究中的先进成像技术。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-19 DOI: 10.1039/d5fd90025e

Fabio Nudelman, Roland Kröger

引用次数: 0

Spiers Memorial Lecture: A retrospective view on the non-classical features revealed by advanced imaging of biominerals. 斯皮尔斯纪念讲座：回顾生物矿物先进成像显示的非经典特征。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-13 DOI: 10.1039/d5fd00054h

Laurie Gower

{"title":"Spiers Memorial Lecture: A retrospective view on the non-classical features revealed by advanced imaging of biominerals.","authors":"Laurie Gower","doi":"10.1039/d5fd00054h","DOIUrl":"https://doi.org/10.1039/d5fd00054h","url":null,"abstract":"Biominerals have unique morphologies and complex hierarchical microstructures, so the study of biomineralization has benefited greatly from the development of advanced microscopy and characterization tools. In my career, I witnessed a revolutionary change in the theories relating to biomineral formation mechanisms. While much of this was due to the advancements in imaging techniques, I present an argument to suggest that in vitro model systems played an important role in steering the biomineral community toward resolving the non-classical crystallization processes that are now understood to lie at the foundation of biological calcification processes. This retrospective review will discuss two case studies that are classic examples of biominerals, mollusk nacre for the invertebrates, and bone for the vertebrates. It will therefore be biased given my group's discovery of the Polymer-Induced Liquid-Precursor (PILP) process, which serendipitously emulated the morphologies and textures of these (and other) biominerals. The goal, however, is not to repeat that body of literature, but rather to demonstrate how the use of model systems has helped decipher mineralization mechanisms, and to propose new ideas that could be explored to further advance the field.","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144289361","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}

引用次数: 0

Convergence in biomineralization patterns across animal eggshells. 动物蛋壳生物矿化模式的趋同。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-12 DOI: 10.1039/d5fd00028a

Gerben Debruyn, Seung Choi, Jessica L Dobson, Yana Maudens, Karen De Clerck, Matthew D Shawkey, Shukang Zhang, Liliana D'Alba

{"title":"Convergence in biomineralization patterns across animal eggshells.","authors":"Gerben Debruyn, Seung Choi, Jessica L Dobson, Yana Maudens, Karen De Clerck, Matthew D Shawkey, Shukang Zhang, Liliana D'Alba","doi":"10.1039/d5fd00028a","DOIUrl":"https://doi.org/10.1039/d5fd00028a","url":null,"abstract":"Shelled eggs are key components of animal reproduction on land, evolving independently in distant lineages of terrestrial animals including nematodes, gastropods, annelids, arthropods and chordates. They perform critical functions such as the exchange of gases between embryo and the environment, desiccation avoidance and protection from harmful radiation, microbial infection and mechanical damage. A core mechanism behind eggshell multifunctionality is the incorporation of biominerals (mainly calcium carbonate and calcium phosphate) into the shell. Very little is known about eggshell structure in invertebrates, but some recent pioneering studies have proposed that similar mineralization patterns may have evolved convergently in eggshells of pulmonate gastropods, some insects, and vertebrates. However, because a detailed characterization of the structural and chemical composition of invertebrate eggshells is not available, it has not been possible to test this hypothesis. Here, we use computed tomography, electron microscopy, electron backscatter diffraction analyses, atomic force microscopy, spectroscopy, and histochemistry to characterize and compare microstructure and chemical composition of pulmonate gastropod, insect and vertebrate eggshells. These techniques revealed the universal presence of an organic matrix in mineralized eggshells. However, disparities in the distribution of calcium throughout the shell, crystallographic orientation that appears random in invertebrates (but not vertebrates), and presence of different calcium types including the rare and unstable vaterite highlight divergence whose functional significance should be the subject of future study.","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144273741","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}

引用次数: 0

Imaging the orientation of hydroxyapatite crystallites across full mouse femora. 羟基磷灰石晶体在整个小鼠股骨上的定向成像。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-11 DOI: 10.1039/d5fd00009b

Thorbjørn Erik Køppen Christensen, Takeshi Moriishi, Toshihisa Komori

{"title":"Imaging the orientation of hydroxyapatite crystallites across full mouse femora.","authors":"Thorbjørn Erik Køppen Christensen, Takeshi Moriishi, Toshihisa Komori","doi":"10.1039/d5fd00009b","DOIUrl":"https://doi.org/10.1039/d5fd00009b","url":null,"abstract":"Imaging the orientations of crystallites in bone requires the usage of synchrotron X-ray radiation, which is a limited resource for researchers. Thus scans have historically been limited to either small regions or few samples. In the present study, we scan 16 full frontal cross sections of mouse femora. This makes it possible to study structure, orientation, and composition, statistically across many different bones and animals, while preserving the structural context. From the following analysis, we can deduce that while the trabecular bone in the shaft has a larger fraction of oriented crystallites than other regions in the bone, the oriented fraction is more well aligned in the cortical bone in the shaft compared to other regions in the bone. We also see that the crystallites in the cortical and trabecular bone are longer than those in the femoral head and the condyle. The study also shows a larger Sr content in the cortical bone compared to other regions, and a larger Zn content in the femoral head compared to other regions of the bones. This study shows the need for and possibility of scanning larger regions to understand bioinorganic materials.","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144264900","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}

引用次数: 0

Fabrication and characterization of phosphoinositide containing asymmetric vesicles in physiological salt. 生理盐中含不对称囊泡磷酸肌苷的制备与表征。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-10 DOI: 10.1039/d4fd00191e

Trevor A Paratore, Alonzo H Ross, Arne Gericke

{"title":"Fabrication and characterization of phosphoinositide containing asymmetric vesicles in physiological salt.","authors":"Trevor A Paratore, Alonzo H Ross, Arne Gericke","doi":"10.1039/d4fd00191e","DOIUrl":"https://doi.org/10.1039/d4fd00191e","url":null,"abstract":"Phosphoinositide (PIPs) lipids mediate a broad range of physiological functions by attracting proteins at specific time points to distinct cellular sites. Many of these processes are associated with the local accumulation of PIPs and PIP/protein signaling platform formation. Studies aimed at determining the physicochemical underpinnings of PIP domain formation have been limited to model systems that exhibited the same lipid composition in both bilayer leaflets. However, biological membranes are asymmetric, and it is desirable to develop an experimental approach that allows for the fabrication of lipid model systems with a non-symmetric lipid bilayer, i.e., a membrane mimic that exhibits a PIP containing lipid mixture in one leaflet and a different lipid composition in the opposing leaflet. We adapted the previously introduced hemifusion method for the fabrication of asymmetric Giant Unilamellar Vesicles (aGUVs) for the fabrication of aGUVs with phosphatidylinositol-(4,5)-bisphosphate (PI(4,5)P2) in a physiological ionic strength buffer solution. The general method involved the bivalent cation-initiated fusion of a symmetric GUV (sGUV) with solid-supported lipid bilayers, which leads to the exchange of the outer leaflet of the sGUV. We find that initiating the hemifusion with 6 mM Ca2+ leads to a low yield and quality of the aGUVs. We attribute this to macroscopic Ca2+/PI(4,5)P2 domain formation of the solid support lipid bilayer (SLB), which leads to the interaction of the sGUVs with regions enriched in PI(4,5)P2 (domain) and other areas that are void of the PIP lipid. Using 6 mM Mg2+ as the initiator instead led to an improvement in terms of yield and aGUV quality. The best results were obtained when using 1 mM Mg2+. We are introducing several data analysis approaches that allow for the identification of aGUVs that exhibit high quality in terms of the outer leaflet exchange and composition of the two aGUV leaflets.","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256853","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}

引用次数: 0

Membrane potential fluctuations and water asymmetry on plasma cell and model lipid membranes: origins, implications and properties. 浆细胞和模型脂质膜上的膜电位波动和水不对称：起源、含义和性质。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-09 DOI: 10.1039/d4fd00197d

Zhi Li, Iwona Swiderska, Lena Dalifoski, Seonwoo Lee, Nelson Alonso Correa-Rojas, David Roesel, Maksim Eremchev, Mischa Flor, Orly B Tarun, Arianna Marchioro, Sylvie Roke

{"title":"Membrane potential fluctuations and water asymmetry on plasma cell and model lipid membranes: origins, implications and properties.","authors":"Zhi Li, Iwona Swiderska, Lena Dalifoski, Seonwoo Lee, Nelson Alonso Correa-Rojas, David Roesel, Maksim Eremchev, Mischa Flor, Orly B Tarun, Arianna Marchioro, Sylvie Roke","doi":"10.1039/d4fd00197d","DOIUrl":"https://doi.org/10.1039/d4fd00197d","url":null,"abstract":"Membrane potential fluctuations have previously been detected using second harmonic (SH) water imaging on neuronal cells and model lipid bilayer membranes. We report that such fluctuations are also visible when membrane potential-sensitive fluorophores are used as contrast agents, and fluctuations are imaged on both free-standing lipid membranes (FLMs) and on the plasma membranes of neuroblastoma cells. We show that upon K+ depolarization, non-uniform recovery responses occur across cells and within single cells. We discuss the origins and implications of such fluctuations, and investigate the molecular-level details of membrane potential distributions on FLMs and compare it to those on giant unilamellar vesicles (GUVs). SH water imaging shows that the hydrated part of lipid membranes is most likely composed of regions having a diffuse double layer, and other regions having an additional condensed double layer, with a high concentration of ions/ionic groups. In terms of transmembrane potential distributions, FLMs and GUVs show similar signatures, as expected from electrostatics. Comparing passive ion transport, FLMs and GUVs of identical composition behave differently, with GUVs being more permeable for proton transport (∼20×). This is likely caused by differences in the hydrophobic cores of the membranes, which create different energetic barriers for the proton transport.","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144245366","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}

引用次数: 0

Crystallisation in biomineral mollusc shell studied by 3D Bragg ptychography. 三维Bragg图谱研究生物矿物软体动物壳的结晶。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-06 DOI: 10.1039/d5fd00020c

Tilman A Grünewald, Peng Li, Julien Duboisset, Julius Nouet, Oier Bikondoa, Jeremie Vidal-Dupiol, Denis Saulnier, Manfred Burghammer, Virginie Chamard

{"title":"Crystallisation in biomineral mollusc shell studied by 3D Bragg ptychography.","authors":"Tilman A Grünewald, Peng Li, Julien Duboisset, Julius Nouet, Oier Bikondoa, Jeremie Vidal-Dupiol, Denis Saulnier, Manfred Burghammer, Virginie Chamard","doi":"10.1039/d5fd00020c","DOIUrl":"https://doi.org/10.1039/d5fd00020c","url":null,"abstract":"Biomineralisation integrates complex biologically assisted physico-chemical processes leading to an extraordinary diversity of calcareous biomineral crystalline architectures, in intriguing contrast with the consistent presence of a submicrometric granular structure. While the repeated observation of amorphous calcium carbonate is interpreted as a precursor to the crystalline phase, the crystalline transition mechanisms are poorly understood. Access to the crystalline architecture at the mesoscale, i.e., over a few granules, is key to building realistic crystallisation models. Here we exploit three-dimensional X-ray Bragg ptychography microscopy to provide a series of nanoscale maps of the crystalline structure within the \"single-crystalline\" prism of the prismatic layer of a Pinctada margaritifera shell. The mesocrystalline organisation exhibits several micrometre-sized iso-oriented/iso-strained crystalline domains, the detailed studies of which reveal the presence of crystalline coherence domains ranging from 130 to 550 nm in size. The further increase in the lattice parameter with the size of the coherence domain likely results from the crystallisation mechanism, pointing towards a maturation process occurring after the initial amorphous-to-crystalline transition.","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144232738","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}

引用次数: 0

Comparative structural analysis of stereom polymorphs in the sea urchin test. 海胆试验中立体多形体的比较结构分析。

IF 3.3 3区化学

Faraday Discussions Pub Date : 2025-06-04 DOI: 10.1039/d5fd00033e

Ronald Seidel, Konrad Handrich, Marie Albéric, Jonathan Perrin, Derk Joester, Yael Politi, Luca Bertinetti

{"title":"Comparative structural analysis of stereom polymorphs in the sea urchin test.","authors":"Ronald Seidel, Konrad Handrich, Marie Albéric, Jonathan Perrin, Derk Joester, Yael Politi, Luca Bertinetti","doi":"10.1039/d5fd00033e","DOIUrl":"https://doi.org/10.1039/d5fd00033e","url":null,"abstract":"The fenestrated ultrastructure of the sea urchin endoskeleton has attracted the attention of researchers in different fields due to its morphological complexity and crystallographic properties. Microscopic calcitic trabeculae form an intricate bicontinuous network, called the stereom. The stereom exhibits a wide variation of pore patterns, but is essentially a single calcite crystal (mono-crystalline). The polymorphism and crystal orientation in the skeletons of sea urchins have both been previously extensively described, mostly for taxonomical reasons and for mechanical studies. Moreover, while the resemblance of the stereom architecture to constant-mean-curvature (CMC) structures has been pointed out, a quantitative description and critical analysis is still lacking. Here, we use synchrotron micro-computed tomography to capture the three-dimensional (3D) architecture of the skeletal stereom in sea urchins for morphological quantification. By characterising the different stereom types, we define a data processing pipeline that allows inter-individual and interspecies comparison of stereom architectures, with implications for sea urchin taxonomy, mechanics, and skeletal growth. We further show that the various stereom morphologies are bicontinuous CMC surfaces that are unconstrained by crystallography. Our results highlight the properties of the soft tissue filling the stereom pore space in defining the shape of sea urchin biocalcite.","PeriodicalId":76,"journal":{"name":"Faraday Discussions","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144214398","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}

引用次数: 0