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FEBS Letters Jan 2023Metalation, the acquisition of metals by proteins, must avoid mis-metalation with tighter binding metals. This is illustrated by four selected proteins that require... (Review)
Review
Metalation, the acquisition of metals by proteins, must avoid mis-metalation with tighter binding metals. This is illustrated by four selected proteins that require different metals: all show similar ranked orders of affinity for bioavailable metals, as described in a universal affinity series (the Irving-Williams series). Crucially, cellular protein metalation occurs in competition with other metal binding sites. The strength of this competition defines the intracellular availability of each metal: its magnitude has been estimated by calibrating a cells' set of DNA-binding, metal-sensing, transcriptional regulators. This has established that metal availabilities (as free energies for forming metal complexes) are maintained to the inverse of the universal series. The tightest binding metals are least available. With these availabilities, correct metalation is achieved.
Topics: Metals; Metalloproteins; Bacterial Proteins; Cobalt; Copper
PubMed: 36124565
DOI: 10.1002/1873-3468.14500 -
Chemical Communications (Cambridge,... Aug 2022Surface patterning of inorganic nanoparticles through site-selective functionalization with mixed-ligand shells or additional inorganic material is an intriguing... (Review)
Review
Surface patterning of inorganic nanoparticles through site-selective functionalization with mixed-ligand shells or additional inorganic material is an intriguing approach to developing tailored nanomaterials with potentially novel and/or multifunctional properties. The unique physicochemical properties of such nanoparticles are likely to impact their behavior and functionality in biological environments, catalytic systems, and electronics applications, making it vital to understand how we can achieve and characterize such regioselective surface functionalization. This Feature Article will review methods by which chemists have selectively modified the surface of colloidal nanoparticles to obtain both two-sided Janus particles and nanoparticles with patchy or stripey mixed-ligand shells, as well as to achieve directed growth of mesoporous oxide materials and metals onto existing nanoparticle templates in a spatially and compositionally controlled manner. The advantages and drawbacks of various techniques used to characterize the regiospecificity of anisotropic surface coatings are discussed, as well as areas for improvement, and future directions for this field.
Topics: Catalysis; Ligands; Metal Nanoparticles; Metals; Nanoparticles; Nanostructures
PubMed: 35975479
DOI: 10.1039/d2cc03603g -
The Biochemical Journal Mar 2021Metal ions play many critical roles in biology, as structural and catalytic cofactors, and as cell regulatory and signalling elements. The metal-protein affinity,... (Review)
Review
Metal ions play many critical roles in biology, as structural and catalytic cofactors, and as cell regulatory and signalling elements. The metal-protein affinity, expressed conveniently by the metal dissociation constant, KD, describes the thermodynamic strength of a metal-protein interaction and is a key parameter that can be used, for example, to understand how proteins may acquire metals in a cell and to identify dynamic elements (e.g. cofactor binding, changing metal availabilities) which regulate protein metalation in vivo. Here, we outline the fundamental principles and practical considerations that are key to the reliable quantification of metal-protein affinities. We review a selection of spectroscopic probes which can be used to determine protein affinities for essential biological transition metals (including Mn(II), Fe(II), Co(II), Ni(II), Cu(I), Cu(II) and Zn(II)) and, using selected examples, demonstrate how rational probe selection combined with prudent experimental design can be applied to determine accurate KD values.
Topics: Animals; Catalysis; Humans; Metals; Protein Binding; Proteins; Thermodynamics
PubMed: 33710331
DOI: 10.1042/BCJ20200838 -
Small (Weinheim An Der Bergstrasse,... May 2022Transparent electrodes (TEs) are pivotal components in many modern devices such as solar cells, light-emitting diodes, touch screens, wearable electronic devices, smart... (Review)
Review
Transparent electrodes (TEs) are pivotal components in many modern devices such as solar cells, light-emitting diodes, touch screens, wearable electronic devices, smart windows, and transparent heaters. Recently, the high demand for flexibility and low cost in TEs requires a new class of transparent conductive materials (TCMs), serving as substitutes for the conventional indium tin oxide (ITO). So far, ITO has been the most used TCM despite its brittleness and high cost. Among the different emerging alternative materials to ITO, metallic nanomaterials have received much interest due to their remarkable optical-electrical properties, low cost, ease of manufacturing, flexibility, and widespread applicability. These involve metal grids, thin oxide/metal/oxide multilayers, metal nanowire percolating networks, or nanocomposites based on metallic nanostructures. In this review, a comparison between TCMs based on metallic nanomaterials and other TCM technologies is discussed. Next, the different types of metal-based TCMs developed so far and the fabrication technologies used are presented. Then, the challenges that these TCMs face toward integration in functional devices are discussed. Finally, the various fields in which metal-based TCMs have been successfully applied, as well as emerging and potential applications, are summarized.
Topics: Electric Conductivity; Electrodes; Metals; Nanostructures; Nanowires; Oxides
PubMed: 35195360
DOI: 10.1002/smll.202106006 -
Journal of Materials Chemistry. B Feb 2022Liquid metals (LMs) not only retain the basic properties of metallic biomaterials, such as high thermal conductivity and high electrical conductivity, but also possess... (Review)
Review
Liquid metals (LMs) not only retain the basic properties of metallic biomaterials, such as high thermal conductivity and high electrical conductivity, but also possess flexibility, flowability, deformability, plasticity, good adhesion, and so on. Therefore, they open many possibilities of extending soft metals into biomedical sciences including biomedical imaging. One of the special properties of LMs is that they can provide a controllable material system in which the electrical, thermal, mechanical, and chemical properties can be controlled on a large scale. This paper reviews the preparation and characteristics of LM-based biomaterials classified into four categories: LM micro/nanoparticles, surface modified LM droplets, LM composites with inorganic substances, and LM composites with organic polymers. Besides, considering the most important requirement for biomaterials is biocompatibility, the paper also analyzes the toxicity results of various LM biomaterials when used in the biomedical area, from different levels including body weight measurement, histology evaluation, and blood biochemistry tests. Next, the applications of LMs in X-ray, CT, MRI, photoacoustic imaging, and molecular imaging are introduced in detail. And finally, the challenges and opportunities of their application in medical imaging are also discussed.
Topics: Biocompatible Materials; Electric Conductivity; Metals; Polymers
PubMed: 35048099
DOI: 10.1039/d1tb02399c -
Current Opinion in Genetics &... Dec 2022Metal ions are potent catalysts and have been available for cellular biochemistry at all stages of evolution. Growing evidence suggests that metal catalysis was critical... (Review)
Review
Metal ions are potent catalysts and have been available for cellular biochemistry at all stages of evolution. Growing evidence suggests that metal catalysis was critical for the origin of the very first metabolic reactions. With approximately 80% of modern metabolic pathways being dependent on metal ions, metallocatalysis and homeostasis continue to be essential for intracellular metabolic networks and physiology. However, the genetic network that controls metal ion homeostasis and the impact of metal availability on metabolism is poorly understood. Here, we review recent work on gene and protein evolution relevant for better understanding metal ion biology and its role in metabolism. We highlight the importance of analysing the origin and evolution of enzyme catalysis in the context of catalytically relevant metal ions, summarise unanswered questions essential for developing a comprehensive understanding of metal ion homeostasis and advocate for the consideration of metal ion properties and availability in the design and directed evolution of novel enzymes and pathways.
Topics: Gene Regulatory Networks; Ions; Metals; Homeostasis; Catalysis
PubMed: 36183585
DOI: 10.1016/j.gde.2022.101987 -
Biosensors Nov 2020Biosensors are the core elements for obtaining significant physiological information from living organisms. To better sense life information, flexible biosensors and... (Review)
Review
Biosensors are the core elements for obtaining significant physiological information from living organisms. To better sense life information, flexible biosensors and implantable sensors that are highly compatible with organisms are favored by researchers. Moreover, materials for preparing a new generation of flexible sensors have also received attention. Liquid metal is a liquid-state metallic material with a low melting point at or around room temperature. Owing to its high electrical conductivity, low toxicity, and superior fluidity, liquid metal is emerging as a highly desirable candidate in biosensors. This paper is dedicated to reviewing state-of-the-art applications in biosensors that are expounded from seven aspects, including pressure sensor, strain sensor, gas sensor, temperature sensor, electrical sensor, optical sensor, and multifunctional sensor, respectively. The fundamental scientific and technological challenges lying behind these recommendations are outlined. Finally, the perspective of liquid metal-based biosensors is present, which stimulates the upcoming design of biosensors.
Topics: Biosensing Techniques; Equipment Design; Metals; Prostheses and Implants; Wearable Electronic Devices
PubMed: 33182535
DOI: 10.3390/bios10110170 -
International Journal of Nanomedicine 2022Across the planet, outbreaks of bacterial illnesses pose major health risks and raise concerns. Photodynamic, photothermal, and metal ion release effects of transition... (Review)
Review
Across the planet, outbreaks of bacterial illnesses pose major health risks and raise concerns. Photodynamic, photothermal, and metal ion release effects of transition metal-based nanocomposites (TMNs) were recently shown to be highly effective in reducing bacterial resistance and upsurges in outbreaks. Surface plasmonic resonance, photonics, crystal structures, and optical properties of TMNs have been used to regulate metal ion release, produce oxidative stress, and generate heat for bactericidal applications. The superior properties of TMNs provide a chance to investigate and improve their antimicrobial actions, perhaps leading to therapeutic interventions. In this review, we discuss three alternative antibacterial strategies based on TMNs of photodynamic therapy, photothermal therapy, and metal ion release and their mechanistic actions. The scientific community has made significant efforts to address the safety, effectiveness, toxicity, and biocompatibility of these metallic nanostructures; significant achievements and trends have been highlighted in this review. The combination of therapies together has borne significant results to counter antimicrobial resistance (4-log reduction). These three antimicrobial pathways are separated into subcategories based on recent successes, highlighting potential needs and challenges in medical, environmental, and allied industries.
Topics: Nanocomposites; Anti-Bacterial Agents; Anti-Infective Agents; Transition Elements; Metals
PubMed: 36605560
DOI: 10.2147/IJN.S392081 -
Magnetic Resonance Imaging Clinics of... Nov 2022Postoperative MR imaging of joints is now commonly requested, yet artifacts caused by metallic orthopedic implants remain a significant challenge during image... (Review)
Review
Postoperative MR imaging of joints is now commonly requested, yet artifacts caused by metallic orthopedic implants remain a significant challenge during image interpretation. Effective artifact reduction is essential to identify postsurgical complications, such as prosthesis loosening, infection, adverse local tissue reaction, and periarticular soft tissue injuries. This article reviews basic and advanced metal artifact reduction MR imaging techniques applied to various clinical protocols for successful postoperative MR imaging of small and large joints.
Topics: Artifacts; Humans; Magnetic Resonance Imaging; Metals; Prostheses and Implants
PubMed: 36243506
DOI: 10.1016/j.mric.2022.03.002 -
Chemical Communications (Cambridge,... Jul 2023A wide variety of synthetic methods have been developed for the synthesis of functionalized aliphatic amines because of their broad utility in both synthetic and... (Review)
Review
A wide variety of synthetic methods have been developed for the synthesis of functionalized aliphatic amines because of their broad utility in both synthetic and medicinal chemistry. The synthesis of functionalized aliphatic amines direct C-H functionalization of readily available aliphatic amines, the majority of which rely on the use of metallic reagents/catalysts and hazardous oxidants, is advantageous in comparison to the classical multistep approaches. However, the scope to carry out such direct C-H functionalization of aliphatic amines under metal and oxidant-free conditions is being continuously explored. As a result, the examples of C-H functionalization of aliphatic amines employing iminium/azonium ions, which are formed classical condensation of amines and carbonyl/nitroso compounds, are on the rise. This article summarizes the recent developments in the iminium and azonium-activated metal and oxidant-free C-H functionalization of aliphatic amines with the main focus on the intermolecular reactions of iminium/azonium ions, enamines, and zwitterions with suitable nucleophiles, electrophiles and dipolarophiles.
Topics: Oxidants; Amines; Metals; Catalysis
PubMed: 37340857
DOI: 10.1039/d3cc01299a