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Biosensors Aug 2023Cancer is a common illness with a high mortality. Compared with traditional technologies, biomarker detection, with its low cost and simple operation, has a higher... (Review)
Review
Cancer is a common illness with a high mortality. Compared with traditional technologies, biomarker detection, with its low cost and simple operation, has a higher sensitivity and faster speed in the early screening and prognosis of cancer. Therefore, extensive research has focused on the development of biosensors and the construction of sensing interfaces. Molybdenum disulfide (MoS) is a promising two-dimensional (2D) nanomaterial, whose unique adjustable bandgap shows excellent electronic and optical properties in the construction of biosensor interfaces. It not only has the advantages of a high catalytic activity and low manufacturing costs, but it can also further expand the application of hybrid structures through different functionalization, and it is widely used in various biosensors fields. Herein, we provide a detailed introduction to the structure and synthesis methods of MoS, and explore the unique properties and advantages/disadvantages exhibited by different structures. Specifically, we focus on the excellent properties and application performance of MoS and its composite structures, and discuss the widespread application of MoS in cancer biomarkers detection from both electrochemical and optical dimensions. Additionally, with the cross development of emerging technologies, we have also expanded the application of other emerging sensors based on MoS for early cancer diagnosis. Finally, we summarized the challenges and prospects of MoS in the synthesis, functionalization of composite groups, and applications, and provided some insights into the potential applications of these emerging nanomaterials in a wider range of fields.
Topics: Biomarkers, Tumor; Molybdenum; Catalysis; Electronics; Neoplasms
PubMed: 37754082
DOI: 10.3390/bios13090848 -
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 -
Environmental Health and Preventive... May 2019Melanin is detectable in various sense organs including the skin in animals. It has been reported that melanin adsorbs toxic elements such as mercury, cadmium, and lead....
BACKGROUND
Melanin is detectable in various sense organs including the skin in animals. It has been reported that melanin adsorbs toxic elements such as mercury, cadmium, and lead. In this study, we investigated the adsorption of molybdenum, which is widely recognized as a toxic element, by melanin.
METHODS
Molybdenum level of the mouse skin was measured by inductively coupled plasma mass spectrometry. The pigmentation level of murine skin was digitalized as the L* value by using a reflectance spectrophotometer. An in vitro adsorption assay was performed to confirm the interaction between molybdenum and melanin.
RESULTS
Our analysis of hairless mice with different levels of skin pigmentation showed that the level of molybdenum increased with an increase in the level of skin pigmentation (L* value). Moreover, our analysis by Spearman's correlation coefficient test showed a strong correlation (r = - 0.9441, p < 0.0001) between L* value and molybdenum level. Our cell-free experiment using the Langmuir isotherm provided evidence for the adsorption of molybdenum by melanin. The maximum adsorption capacity of 1 mg of synthetic melanin for molybdenum was 131 μg in theory.
CONCLUSION
Our in vivo and in vitro results showed a new aspect of melanin as an adsorbent of molybdenum.
Topics: Adsorption; Animals; Melanins; Mice; Mice, Hairless; Mice, Transgenic; Molybdenum; Skin; Skin Pigmentation; Water Pollutants, Chemical
PubMed: 31101002
DOI: 10.1186/s12199-019-0791-y -
Protein Science : a Publication of the... Jan 2019An overview is provided of the molybdenum- and tungsten-containing enzymes that catalyze the interconversion of formate and CO , focusing on common structural and...
An overview is provided of the molybdenum- and tungsten-containing enzymes that catalyze the interconversion of formate and CO , focusing on common structural and mechanistic themes, as well as a consideration of the manner in which the mature Mo- or W-containing cofactor is inserted into apoprotein.
Topics: Aldehyde Oxidoreductases; Catalysis; Coenzymes; Formate Dehydrogenases; Molybdenum; Structure-Activity Relationship; Tungsten
PubMed: 30120799
DOI: 10.1002/pro.3498 -
Inorganic Chemistry Sep 2022The complex [TEA][Tp*Mo(O)(SBMOPP)] () [TEA = tetraethylammonium, Tp* = tris(3,5-dimethylpyrazolyl)hydroborate, and BMOPP = 6-(3-butynyl-2-methyl-2-ol)-2-pivaloyl...
The complex [TEA][Tp*Mo(O)(SBMOPP)] () [TEA = tetraethylammonium, Tp* = tris(3,5-dimethylpyrazolyl)hydroborate, and BMOPP = 6-(3-butynyl-2-methyl-2-ol)-2-pivaloyl pterin] is a structural analogue of the molybdenum cofactor common to all pyranopterin molybdenum enzymes because it possesses a pyranopterin-ene-1,2-dithiolate ligand (SBMOPP) that exists primarily in the ring-closed pyrano structure as a resonance hybrid of ene-dithiolate and thione-thiolate forms. Compound , the protonated [Tp*Mo(O)(SBMOPP-H)] () and one-electron-oxidized [Tp*Mo(O)(SBMOPP)] [] species have been studied using a combination of electrochemistry, electronic absorption, and electron paramagnetic resonance (EPR) spectroscopy. Additional insight into the nature of these molecules has been derived from electronic structure computations. Differences in dithiolene C-S bond lengths correlate with relative contributions from both ene-dithiolate and thione-thiolate resonance structures. Upon protonation of to form , large spectroscopic changes are observed with transitions assigned as Mo(xy) → pyranopterin metal-to-ligand charge transfer and dithiolene → pyranopterin intraligand charge transfer, respectively, and this underscores a dramatic change in electronic structure between and . The changes in electronic structure that occur upon protonation of are also reflected in a large >300 mV increase in the Mo(V/IV) redox potential for , resulting from the greater thione-thiolate resonance contribution and decreased charge donation that stabilize the Mo(IV) state in with respect to one-electron oxidation. EPR spin Hamiltonian parameters for one-electron-oxidized and uncyclized [Tp*Mo(O)(SBDMPP)] [] [BDMPP = 6-(3-butynyl-2,2-dimethyl)-2-pivaloyl pterin] are very similar to each other and to those of [Tp*MoO(bdt)] (bdt = 1,2-ene-dithiolate). This indicates that the dithiolate form of the ligand dominates at the Mo(V) level, consistent with the demand for greater S → Mo charge donation and a corresponding increase in Mo-S covalency as the oxidation state of the metal is increased. Protonation of represents a simple reaction that models how the transfer of a proton from neighboring acidic amino acid residues to the Mo cofactor at a nitrogen atom within the pyranopterin dithiolene (PDT) ligand in pyranopterin molybdenum enzymes can impact the electronic structure of the Mo-PDT unit. This work also illustrates how pyran ring-chain tautomerization drives changes in resonance contributions to the dithiolene chelate and may adjust the reduction potential of the Mo ion.
Topics: Electron Spin Resonance Spectroscopy; Ligands; Molybdenum; Pterins; Thiones
PubMed: 36000991
DOI: 10.1021/acs.inorgchem.2c01234 -
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 -
Contrast Media & Molecular Imaging 2022The study investigates the diagnostic efficacy of ultrasound combined with the molybdenum target mode in breast cancer staging and the relationship between blood flow...
Differential Efficacy of B-Ultrasound Combined with Molybdenum Target Detection Mode for Breast Cancer Staging and Correlation of Blood Flow Parameters with IGF-1 and IGF-2 Expression Level and Prognosis.
The study investigates the diagnostic efficacy of ultrasound combined with the molybdenum target mode in breast cancer staging and the relationship between blood flow parameters and the expression of insulin-like growth factor 1 (IGF-1) and factor 2 (IGF-2) and prognosis. A total of 96 patients admitted to hospital from January 2020 to January 2021 are included in the breast cancer group, and 58 patients admitted to our hospital during the same period are included in the control group, who are diagnosed with benign breast lesions. All patients receive clinicopathological diagnosis, ultrasound detection, and X-ray molybdenum detection. Ultrasound detection, molybdenum target detection, ultrasound combined with the molybdenum target detection mode, and clinicopathological diagnosis results are compared. B-ultrasound combined with the molybdenum target detection mode has high efficiency in diagnosing breast cancer and differentiating pathological stages. Besides, blood flow parameters of patients are closely related to IGF-1 and IGF-2, and IGF-1 and IGF-2 expressions are closely related to the prognosis of patients. Subsequent diagnosis of the disease degree of breast cancer patients can be carried out by ultrasound combined with the molybdenum target detection mode. In addition, the expression of IGF-1 and IGF-2 in patients can be monitored to improve the clinical diagnosis and treatment plan to improve the prognosis of patients, which has a high clinical application value and is worth promoting.
Topics: Breast Neoplasms; Female; Humans; Insulin-Like Growth Factor I; Insulin-Like Growth Factor II; Molybdenum; Neoplasm Staging; Prognosis
PubMed: 35845730
DOI: 10.1155/2022/9198626 -
Molecules (Basel, Switzerland) Oct 2023Sulfite oxidase is one of five molybdenum-containing enzymes known in eukaryotes where it catalyzes the oxidation of sulfite to sulfate. This review covers the history... (Review)
Review
Sulfite oxidase is one of five molybdenum-containing enzymes known in eukaryotes where it catalyzes the oxidation of sulfite to sulfate. This review covers the history of sulfite oxidase research starting out with the early years of its discovery as a hepatic mitochondrial enzyme in vertebrates, leading to basic biochemical and structural properties that have inspired research for decades. A personal view on sulfite oxidase in plants, that sulfates are assimilated for their de novo synthesis of cysteine, is presented by Ralf Mendel with numerous unexpected findings and unique properties of this single-cofactor sulfite oxidase localized to peroxisomes. Guenter Schwarz connects his research to sulfite oxidase via its deficiency in humans, demonstrating its unique role amongst all molybdenum enzymes in humans. In essence, in both the plant and animal kingdoms, sulfite oxidase represents an important player in redox regulation, signaling and metabolism, thereby connecting sulfur and nitrogen metabolism in multiple ways.
Topics: Animals; Humans; Sulfite Oxidase; Molybdenum; Sulfites; Plants; Molybdenum Cofactors; Sulfates
PubMed: 37836841
DOI: 10.3390/molecules28196998 -
The Journal of Nutrition Apr 2006In this study we developed an expanded compartmental model of molybdenum (Mo) kinetics to determine rates of molybdenum distribution during molybdenum depletion and...
In this study we developed an expanded compartmental model of molybdenum (Mo) kinetics to determine rates of molybdenum distribution during molybdenum depletion and repletion. The model was based on a clinical study in which 4 men consumed a low-molybdenum diet of 22 microg/d (0.23 micromol/d) for 102 d, followed by a high molybdenum diet of 467 microg/d (4.9 micromol/d) for 18 d. Stable isotopes 100Mo and 97Mo were administered orally and intravenously, respectively, at several time points during the study, and serial samples of plasma, urine, and feces were analyzed for 100Mo, 97Mo, and total Mo. Based on plasma, urine, and fecal molybdenum levels, kinetic parameters of distribution and elimination were determined. The rates of molybdenum distribution and elimination were different during depletion and repletion. During high intake, urinary molybdenum excretion was greater than during low intake. In addition, fractional tissue storage of molybdenum was lower during high intake than during low intake. This suggests that low intake results in an adaptation to conserve body Mo, and that high intake results in an adaptation to eliminate Mo. The model also suggested that food-bound molybdenum was approximately 16% less bioavailable than purified Mo. Finally, under the conditions of this study, the model suggested that an intake of 43 microg/d (0.45 micromol/d) would be sufficient to maintain plasma molybdenum levels at steady state. This is a minimum estimate because subjects in this study were in a molybdenum-sparing state. These findings provide an understanding of the adaptations in molybdenum metabolism that take place during depletion and repletion.
Topics: Adult; Diet; Feces; Humans; Isotopes; Kinetics; Male; Models, Biological; Molybdenum; Tissue Distribution
PubMed: 16549456
DOI: 10.1093/jn/136.4.953 -
Angewandte Chemie (International Ed. in... Oct 2022The biological process of dinitrogen reduction to ammonium occurs at the cofactors of nitrogenases, the only enzymes that catalyze this challenging chemical reaction....
The biological process of dinitrogen reduction to ammonium occurs at the cofactors of nitrogenases, the only enzymes that catalyze this challenging chemical reaction. Three types of nitrogenases have been described, named according to the heterometal in their cofactor: molybdenum, vanadium or iron nitrogenases. Spectroscopic and structural characterization allowed the unambiguous identification of the cofactors of molybdenum and vanadium nitrogenases and revealed a central μ -carbide in both of them. Although genetic studies suggested that the cofactor of the iron nitrogenase contains a similar Fe C core, this has not been experimentally demonstrated. Here we report Valence-to-Core X-ray Emission Spectroscopy providing experimental evidence that this cofactor contains a carbide, thereby making the Fe C core a feature of all nitrogenase cofactors.
Topics: Ammonium Compounds; Iron; Molybdenum; Nitrogenase; Oxidation-Reduction; Vanadium
PubMed: 35975943
DOI: 10.1002/anie.202209190