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Journal of Controlled Release :... Aug 2022Bacterial infections are yet another serious threat to human health. Misuse or overuse of conventional antibiotics has led to the arrival of various super resistant... (Review)
Review
Bacterial infections are yet another serious threat to human health. Misuse or overuse of conventional antibiotics has led to the arrival of various super resistant bacteria along with many serious side effects to human body. In this exigent circumstance, the use of nanomaterial based antibacterial agents is one of the most appropriate solutions to fight against bacteria thereby causing an inhibition to bacterial proliferation. Recent studies show that, due to the large surface area, high biocompatibility, strong near-infrared (NIR) absorption and low cytotoxicity, molybdenum disulphide (MoS), an extraordinary member in the transition metal dichalcogenides (TMDs) is extensively explored in the obliteration of many drug resistant bacteria, photothermal therapy and drug delivery. MoS based nanomaterials can effectively prevent bacterial growth through many mechanisms. Through this review, we have tried to provide an inclusive knowledge on the recent progress of antibacterial studies in MoS based nanomaterials including MoS nanosheets, nanoflowers, quantum dot (QD), hybrid nanocomposites and polymer nanocomposites. Moreover, toxicity of MoS based nanomaterials is described at the end of the review.
Topics: Anti-Bacterial Agents; Disulfides; Drug Delivery Systems; Humans; Molybdenum; Nanocomposites; Polymers
PubMed: 35662576
DOI: 10.1016/j.jconrel.2022.05.047 -
Molecules (Basel, Switzerland) Sep 2022Formate dehydrogenases (FDH) reversibly catalyze the interconversion of CO to formate. They belong to the family of molybdenum and tungsten-dependent oxidoreductases.... (Review)
Review
Formate dehydrogenases (FDH) reversibly catalyze the interconversion of CO to formate. They belong to the family of molybdenum and tungsten-dependent oxidoreductases. For several decades, scientists have been synthesizing structural and functional model complexes inspired by these enzymes. These studies not only allow for finding certain efficient catalysts but also in some cases to better understand the functioning of the enzymes. However, FDH models for catalytic CO reduction are less studied compared to the oxygen atom transfer (OAT) reaction. Herein, we present recent results of structural and functional models of FDH.
Topics: Carbon Dioxide; Formate Dehydrogenases; Formates; Molybdenum; Oxidation-Reduction; Oxygen; Tungsten
PubMed: 36144724
DOI: 10.3390/molecules27185989 -
Metal Ions in Life Sciences Mar 2020The last 20 years have seen a dramatic increase in our mechanistic understanding of the reactions catalyzed by pyranopterin Mo and W enzymes. These enzymes possess a...
The last 20 years have seen a dramatic increase in our mechanistic understanding of the reactions catalyzed by pyranopterin Mo and W enzymes. These enzymes possess a unique cofactor (Moco) that contains a novel ligand in bioinorganic chemistry, the pyranopterin ene-1,2-dithiolate. A synopsis of Moco biosynthesis and structure is presented, along with our current understanding of the role Moco plays in enzymatic catalysis. Oxygen atom transfer (OAT) reactivity is discussed in terms of breaking strong metal-oxo bonds and the mechanism of OAT catalyzed by enzymes of the sulfite oxidase (SO) family that possess dioxo Mo(VI) active sites. OAT reactivity is also discussed in members of the dimethyl sulfoxide (DMSO) reductase family, which possess des-oxo Mo(IV) sites. Finally, we reveal what is known about hydride transfer reactivity in xanthine oxidase (XO) family enzymes and the formate dehydrogenases. The formal hydride transfer reactivity catalyzed by xanthine oxidase family enzymes is complex and cleaves substrate C-H bonds using a mechanism that is distinct from monooxygenases. The chapter primarily highlights developments in the field that have occurred since ~2000, which have contributed to our collective structural and mechanistic understanding of the three canonical pyranopterin Mo enzymes families: XO, SO, and DMSO reductase.
Topics: Biocatalysis; Molybdenum; Sulfite Oxidase; Tungsten
PubMed: 32851830
DOI: 10.1515/9783110589757-015 -
ACS Applied Bio Materials Jul 2023Molybdenum-based nanomaterials with variable oxidation states can be developed as nanozyme catalysts. In this work, we developed a one-pot method for the preparation of...
Molybdenum-based nanomaterials with variable oxidation states can be developed as nanozyme catalysts. In this work, we developed a one-pot method for the preparation of molybdenum disulfide assisted by protein. Protamine was used as a cationic template to link molybdate anions and form complexes. During hydrothermal synthesis, protamine can affect the nucleation process of molybdenum disulfide and inhibit their aggregation, which facilitates the fabrication of small-sized molybdenum disulfide nanoparticles. Moreover, the abundant amino/guanidyl groups of protamine could both physically adsorb and chemically bond to molybdenum disulfide and further modulate the crystal structures. The optimized size and crystalline structure enabled a higher exposure of active sites, which enhanced the peroxidase-like activity of molybdenum disulfide/protamine nanocomposites. Meanwhile, the antibacterial activity of protamine was retained in the molybdenum disulfide/protamine nanocomposites, which could synergize with the peroxidase-like activity of molybdenum disulfide to kill bacteria. Therefore, the molybdenum disulfide/protamine nanocomposites are good candidates for antibacterial agents with lower chances of antimicrobial resistance. This study establishes an easy way to design artificial nanozymes by compounding suitable components.
Topics: Molybdenum; Biomimetics; Nanocomposites; Protamines; Peroxidases; Anti-Bacterial Agents
PubMed: 37317061
DOI: 10.1021/acsabm.3c00341 -
Small (Weinheim An Der Bergstrasse,... Aug 2022The disulfide compounds of molybdenum (MoS ) are layered van der Waals materials that exhibit a rich array of polymorphic structures. MoS can be roughly divided into... (Review)
Review
The disulfide compounds of molybdenum (MoS ) are layered van der Waals materials that exhibit a rich array of polymorphic structures. MoS can be roughly divided into semiconductive phase and metallic phase according to the difference in electron filling state of the 4d orbital of Mo atom. The two phases show completely different properties, leading to their diverse applications in biosensors. But to some extent, they compensate for each other. This review first introduces the relationship between phase state and the chemical/physical structures and properties of MoS . Furthermore, the synthetic methods are summarized and the preparation strategies for metastable phases are highlighted. In addition, examples of electronic and chemical property designs of MoS by means of doping and surface modification are outlined. Finally, studies on biosensors based on MoS in recent years are presented and classified, and the roles of MoS with different phases are highlighted. This review offers references for the selection of materials to construct different types of biosensors based on MoS , and provides inspiration for sensing performance enhancement.
Topics: Biosensing Techniques; Disulfides; Molybdenum
PubMed: 35908166
DOI: 10.1002/smll.202202956 -
Journal of Materials Chemistry. B Apr 2022Molybdenum disulfide (MoS) nanostructures have recently earned substantial thoughts from the scientific communities owing to their unique physicochemical, optical and... (Review)
Review
Molybdenum disulfide (MoS) nanostructures have recently earned substantial thoughts from the scientific communities owing to their unique physicochemical, optical and electrical properties. Although MoS has been mostly highlighted for its industrial applications, its biological applicability has not been extensively explored. The introduction of nanotechnology in the field of tissue engineering has significantly contributed to human welfare by displaying advancement in tissue regeneration. Assimilation of MoS nanostructures into the polymer matrix has been considered a persuasive material of choice for futuristic tissue engineering applications. The current review provides a general discussion on the structural properties of different MoS nanostructures. Further, this article focuses on the interactions of MoS with biological systems in terms of its cellular toxicity, and biocompatibility along with its capability for cell proliferation, adhesion, and immunomodulation. The article continues to confer the utility of MoS nanostructure-based scaffolds for various tissue engineering applications. The article also highlights some emerging prospects and possibilities of the applicability of MoS-based nanostructures in large organ tissue engineering. Finally, the article concludes with a brief annotation on the challenges and limitations that need to be overcome in order to make plentiful use of this wonderful material for tissue engineering applications.
Topics: Disulfides; Humans; Molybdenum; Nanostructures; Tissue Engineering
PubMed: 35262167
DOI: 10.1039/d2tb00131d -
The Journal of Biological Chemistry Mar 2022Sulfite oxidase (SOX) is a homodimeric molybdoheme enzyme that oxidizes sulfite to sulfate at the molybdenum center. Following substrate oxidation, molybdenum is reduced...
Sulfite oxidase (SOX) is a homodimeric molybdoheme enzyme that oxidizes sulfite to sulfate at the molybdenum center. Following substrate oxidation, molybdenum is reduced and subsequently regenerated by two sequential electron transfers (ETs) via heme to cytochrome c. SOX harbors both metals in spatially separated domains within each subunit, suggesting that domain movement is necessary to allow intramolecular ET. To address whether one subunit in a SOX dimer is sufficient for catalysis, we produced heterodimeric SOX variants with abolished sulfite oxidation by replacing the molybdenum-coordinating and essential cysteine in the active site. To further elucidate whether electrons can bifurcate between subunits, we truncated one or both subunits by deleting the heme domain. We generated three SOX heterodimers: (i) SOX/Mo with two active molybdenum centers but one deleted heme domain, (ii) SOX/Mo_C264S with one unmodified and one inactive subunit, and (iii) SOX_C264S/Mo harboring a functional molybdenum center on one subunit and a heme domain on the other subunit. Steady-state kinetics showed 50% SOX activity for the SOX/Mo and SOX/Mo_C264S heterodimers, whereas SOX_C264S/Mo activity was reduced by two orders of magnitude. Rapid reaction kinetics monitoring revealed comparable ET rates in SOX/Mo, SOX/Mo_C264S, and SOX/SOX, whereas in SOX_C264S/Mo, ET was strongly compromised. We also combined a functional SOX Mo domain with an inactive full-length SOX R217W variant and demonstrated interdimer ET that resembled SOX_C264S/Mo activity. Collectively, our results indicate that one functional subunit in SOX is sufficient for catalysis and that electrons derived from either Mo or Mo follow this path.
Topics: Electrons; Heme; Molybdenum; Protein Domains; Sulfite Oxidase; Sulfites
PubMed: 35120924
DOI: 10.1016/j.jbc.2022.101668 -
Journal of Hazardous Materials Feb 2020Bacterial infection is a serious problem threatening human health. The chitosan (CS)-modified MoS coating loaded with silver nanoparticles (Ag NPs) was designed on the...
Bacterial infection is a serious problem threatening human health. The chitosan (CS)-modified MoS coating loaded with silver nanoparticles (Ag NPs) was designed on the surface of titanium (Ti) to kill bacteria rapidly and efficiently under 660 nm visible light. Ag/MoS exhibited high photocatalytic activity due to the rapid transfer of photo-inspired electrons from MoS to Ag NPs, resulting in higher yields of radical oxygen species (ROS) to kill bacteria. The covering of CS made the composite coating positively charged to further enhance the antibacterial property of the coating. In addition, CS/Ag/MoS-Ti also showed a certain photothermal effect. in vitro results showed that the antibacterial efficiency of the coating on Staphylococcus aureus and Escherichia coli was 98.66% and 99.77% respectively, when the coating was irradiated by 660 nm visible light for 20 min. Cell culture tests showed that CS/Ag/MoS-Ti had no adverse effects on cell growth. Hence, this surface system will be a very promising strategy for eliminating bacterial infection on biomedical device and implants safely and effectively within a short time.
Topics: Anti-Bacterial Agents; Chitosan; Disulfides; Escherichia coli; Light; Microbial Sensitivity Tests; Molybdenum; Photochemistry; Silver; Staphylococcus aureus
PubMed: 31518801
DOI: 10.1016/j.jhazmat.2019.121122 -
Ecotoxicology and Environmental Safety Dec 2022Chromium (Cr) is a harmful heavy metal that poses a serious threat to plants and animals. Selenium (Se) and molybdenum (Mo) are two beneficial elements for plant growth...
Chromium (Cr) is a harmful heavy metal that poses a serious threat to plants and animals. Selenium (Se) and molybdenum (Mo) are two beneficial elements for plant growth and resistance. However, their interactive effects on Cr uptake and distribution are poorly understood. Therefore, a hydroponics experiment was conducted to explore the effects of the use of Se and Mo alone and simultaneously on mitigating Cr toxicity. In this study, Nicotiana tabacum L. seedlings were exposed to control, 50 µM Cr, 50 μM Cr + 2 μM Se, 50 μM Cr + 1 μM Mo, or 50 μM Cr + 2 μM Se + 1 μM Mo in Hoagland solution. After 2 weeks, the plant biomass, Cr, Se and Mo contents, photosynthesis, leaf ultrastructure, antioxidant system, subcellular distribution and associated gene expression in Nicotiana tabacum L. were determined. The results showed that simultaneous use of Se and Mo promoted tobacco growth under Cr stress, as evidenced by reducing reactive oxygen species (ROS) content and reducing Cr translocation factor (TF) and inducing a 51.3% reduction in Cr content in shoots. Additionally, Se-Mo interactions increased the levels of glutathione (GSH) and phytochelatin (PC) and the distribution of Cr in the cell walls and organelles. Furthermore, the relative expression of PCS1 was upregulated, while those of NtST1 and MSN1 were downregulated. The results concluded that the simultaneous use of Se and Mo effectively alleviated Cr toxicity in Nicotiana tabacum L., which not only offers an efficient way for crops to resist Cr toxicity but also provides evidence for the benefit of Se combined with Mo.
Topics: Animals; Selenium; Molybdenum; Nicotiana; Chromium; Biological Transport; Glutathione
PubMed: 36455352
DOI: 10.1016/j.ecoenv.2022.114312 -
Acta Biomaterialia Apr 2024Cardiac pacing with temporary epicardial pacing wires (TEPW) is used to treat rhythm disturbances after cardiac surgery. Occasionally, TEPW cannot be mechanically...
Cardiac pacing with temporary epicardial pacing wires (TEPW) is used to treat rhythm disturbances after cardiac surgery. Occasionally, TEPW cannot be mechanically extracted and remain in the thorax, where they may rarely cause serious complications like migration and infection. We aim to develop bioresorbable TEPW that will dissolve over time even if postoperative removal is unsuccessful. In the present study, we demonstrate a completely bioresorbable design using molybdenum (Mo) as electric conductor and the resorbable polymers poly(D, L-lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL) for electrically insulating double-coating. We compared the pacing properties of these Mo TEPW demonstrators to conventional steel TEPW in Langendorff-perfused rat hearts and observed similar functionality. In vitro, static immersion tests in simulated body fluid for up to 28 days elucidated the degradation behaviour of uncoated Mo strands and the influence of polymer coating thereon. Degradation was considerably reduced in double-coated Mo TEPW compared to the uncoated and the PLGA-coated condition. Furthermore, we confirmed good biocompatibility of Mo degradation products in the form of low cytotoxicity in cell cultures of human cardiomyocytes and cardiac fibroblasts. STATEMENT OF SIGNIFICANCE: Temporary pacing wires are routinely implanted on the heart surface to treat rhythm disturbances in the days following cardiac surgery. Subsequently, these wires are to be removed. When removal attempts are unsuccessful, wires are cut at skin level and the remainders are left inside the chest. Retained fragments may migrate within the body or become a centre of infection. These complications may be prevented using resorbable pacing wires. We manufactured completely resorbable temporary pacing wires using molybdenum as electrical conductor and assessed their function, degradation and biological compatibility. Our study represents an important step in the development of a safer approach to the treatment of rhythm disturbances after cardiac surgery.
Topics: Humans; Animals; Rats; Cardiac Pacing, Artificial; Pacemaker, Artificial; Molybdenum; Absorbable Implants; Pericardium
PubMed: 38432350
DOI: 10.1016/j.actbio.2024.02.039