M13 Bacteriophage-Assisted Biomineralization of Copper Sulfide

2012 ◽  
Vol 1445 ◽  
Author(s):  
Mohammed Shahriar Zaman ◽  
Elaine D. Haberer

ABSTRACTCombinatorial phage display with a pVIII library of M13 bacteriophage was used to identify a peptide sequence capable of recognition and mineralization of copper sulfide. The six sequences isolated from the final biopanning round were rich in basic, hydrophobic, and polar amino acids compared to the phage display library. The peptide sequence, DTRAPEIV, was used to biomineralize copper sulfide on the pVIII major coat protein thus producing linear chains of nanoparticles. Electron microscopy revealed that the phage was capable of controlling the size of the nucleated nanoparticles in an aqueous solution at room temperature and that the mineralized material was copper sulfide. Phage-templated biomineralization is a low temperature, aqueous-based approach to synthesis of copper sulfide nanoparticles with hierarchical order.

Catalysts ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1238
Author(s):  
Murendeni P. Ravele ◽  
Opeyemi A. Oyewo ◽  
Sam Ramaila ◽  
Lydia Mavuru ◽  
Damian C. Onwudiwe

In this paper, spherical-shaped pure phase djurleite (Cu31S16) and roxbyite (Cu7S4) nanoparticles were prepared by a solvothermal decomposition of copper(II) dithiocarbamate complex in dodecanthiol (DDT). The reaction temperature was used to control the phases of the samples, which were represented as Cu31S16 (120 °C), Cu31S16 (150 °C), Cu7S4 (220 °C), and Cu7S4 (250 °C) and were characterized by using X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM), and absorption spectroscopy. The samples were used as photocatalysts for the degradation of tetracycline (TC) under visible light irradiation. The results of the study showed that Cu7S4 (250 °C) exhibited the best activity in the reaction system with the TC degradation rate of up to 99% within 120 min of light exposure, while the Cu31S16 (120 °C) system was only 46.5% at the same reaction condition. In general, roxbyite Cu7S4 (250 °C) could be considered as a potential catalyst for the degradation of TC in solution.


2000 ◽  
Vol 5 (6) ◽  
pp. 435-440 ◽  
Author(s):  
Woo-Chang Kim ◽  
Hae-Ik Rhee ◽  
Boo-Kil Park ◽  
Kyoung-Ho Suk ◽  
Sang-Hoon Cha

Several new antibacterial agents are currently being developed in response to the emergence of bacterial resistance to existing antibiotic substances. The new agents include compounds that interfere with bacterial membrane function. The peptidoglycan component of the bacterial cell wall is synthesized by glutamate racemase, and this enzyme is responsible for the biosynthesis of d-glutamate, which is an essential component of cell wall peptidoglycan. In this study, we screened a phage display library expressing random dodecapeptides on the surface of bacteriophage against an Escherichia coli glutamate racemase, and isolated specific peptide sequences that bind to the enzyme. Twenty-seven positive phage clones were analyzed, and seven different peptide sequences were obtained. Among them, the peptide sequence His-Pro-Trp-His-Lys-Lys-His-Pro-Asp-Arg-Lys-Thr was found most frequently, suggesting that this peptide might have the highest affinity to glutamate racemase. The positive phage clones and HPWHKKHPDRKT synthetic peptide were able to inhibit glutamate racemase activity in vitro, implying that our peptide inhibitors may be utilized for the molecular design of new potential antibacterial agents targeting cell wall synthesis.


Parasitology ◽  
2011 ◽  
Vol 138 (11) ◽  
pp. 1341-1353 ◽  
Author(s):  
J. HERNÁNDEZ-ROMANO ◽  
M. H. RODRÍGUEZ ◽  
V. PANDO ◽  
J. A. TORRES-MONZÓN ◽  
A. ALVARADO-DELGADO ◽  
...  

SUMMARYThe description of Plasmodium ookinete surface proteins and their participation in the complex process of mosquito midgut invasion is still incomplete. In this study, using phage display, a consensus peptide sequence (PWWP) was identified in phages that bound to the Plasmodium berghei ookinete surface and, in selected phages, bound to actin and enolase in overlay assays with ookinete protein extracts. Actin was localized on the surface of fresh live ookinetes by immunofluorescence and electron microscopy using specific antibodies. The overall results indicated that enolase and actin can be located on the surface of ookinetes, and suggest that they could participate in Plasmodium invasion of the mosquito midgut.


2008 ◽  
Vol 8 (3) ◽  
pp. 1288-1294 ◽  
Author(s):  
Wenshou Wang ◽  
Liang Zhen ◽  
Chengyan Xu ◽  
Baoyou Zhang ◽  
Wenzhu Shao

An environmentally friendly route for the synthesis of hierarchical CaWO4 microspheres with novel morphology at room temperature has been successfully developed. CaCl2 and Na2WO4 were used as reaction regents, and distilled water was used as an environmentally friendly solvent. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence spectroscopy. This green wet-chemical route provides a simple, one-step, low-cost approach for the large-scale synthesis of hierarchical CaWO4 microspheres with relatively uniform diameters of 3–6 μm. The hierarchical microspheres are built up with numerous nanorods with an average diameter of 50 nm, which are radially oriented to the microsphere center. SEM observations of different intermediates indicate the possible growth process, in which the hierarchical structure growth is from nuclei through kayak-like, rod-like, peanut-like, dumbbell-like, and peach-like structures to final microspheres, via "self-assembled preferential end growth" of kayak-like particles in aqueous solution. The hierarchical CaWO4 micro-spheres exhibit a strong, broad blue emission peak of 412 nm.


2009 ◽  
Vol 156 (1-3) ◽  
pp. 52-56 ◽  
Author(s):  
Weixing Wang ◽  
Qing Li ◽  
Hua Lin ◽  
Zhiqian Chen ◽  
Ming Nie ◽  
...  

BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 8191-8201
Author(s):  
Fuqiang Hu ◽  
Yucheng Hu ◽  
Lingling Zhang ◽  
Meixue Gan ◽  
Shangjun Liu ◽  
...  

The aim of this paper was to enhance paper strength in NaOH/thiourea aqueous solution at room temperature. Paper from cotton pulp was saturated with room temperature NaOH/thiourea aqueous solution and placed at a fixed temperature (8, 15, and 20 °C) for a period of time (1 h, 2 h, 4 h, and 6 h). The morphology, X-ray diffraction (XRD), mechanical properties, and density of paper were characterized. The results indicated the paper was self-reinforced. Scanning electron microscopy (SEM) photographs indicated that the structure of the treated papers was increasingly compact with decreasing temperature. The XRD results showed that the crystallinity degree of the paper decreased from 80.0% to 60.0%. The stress at break of the treated papers increased by more than fivefold. The wet tensile strength of the treated papers increased remarkably.


2009 ◽  
Vol 32 (3) ◽  
pp. 206 ◽  
Author(s):  
Jorge I Castañeda-Sánchez ◽  
Everardo Curiel-Quesada ◽  
Miguel Pedrosa-Seres ◽  
Mario E Cancino-Diaz ◽  
Sandra Rodríguez-Martínez ◽  
...  

Purpose: HLA class II, p-36 protein, heat shock protein and retinal antigens have been associated with pars planitis (PP), but their participation in the development of the disease are unknown. A search for new molecules related to PP is necessary. This work focused on the identification of peptides recognized by PP patient sera using the phage display method. Methods: Sera of PP patients were used to isolate peptides fused to M13-phage pIII protein. The response of PP and healthy sera to peptides was determined by ELISA. PCR amplification and sequencing of peptide-encoding fragments from clones with high recognition by PP sera were used to characterize displayed peptides. Results: One hundred clones were randomly selected from a phage display library after three panning rounds using serum proteins from a PP patient. The immunologic response level of 100 clones selected were determined with a major number of patients, it was found that one clone was recognized stronger in PP patients sera than in healthy sera (PP vs. healthy; P < 0.05). The peptide-encoding region of this clone was sequenced and translated. The peptide sequence corresponded to HSEAETGPP. An identical amino acid sequence to HSEAETGPP is found in the human proline-rich transmembrane protein 2 which has not been related with eye diseases. Conclusion: These results suggest that the peptide HSEAETGPP is associated with PP.


Author(s):  
K. Takiyama

The coprecipitation of two sparingly soluble compounds in the aqueous solution has been studied by means of electron microscopy and x-ray diffraction techniques, and the properties of the particles produced by the coprecipitation were discussed as an issue in crystal chemistry. In the present investigation the coprecipitation of barium sulfate and barium carbonate was studied. Both crystals belong to the orthorhombic system. The lattice constants of barium sulfate are ao=8.878, bo=5.450 and co=7.152 Å. Those of barium carbonate are ao=5.314, bo=8.902 and co=6.430 Å. The ratio of the lattice constants of barium sulfate is different from that of barium carbonate. In this investigation, the relation of the morphological properties of the particles with the crystallographic properties of the component compounds was discussed. As the particles became very small when the precipitation was carried out at room temperature, in the present investigation the coprecipitation was done at 80°C to produce larger particles to study the morphological properties of the particles.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
M. Amutha ◽  
P. Lalitha ◽  
M. Jannathul Firdhouse

Nanosilver was synthesized using the aqueous solution of solvent extracts of leaf and stem ofKedrostis foetidissima. Three different methods of formation of silver nanoparticles such as reaction at (i) room temperature, (ii) higher temperature, and (iii) sonication were employed in the present study. The synthesized silver nanoparticles were characterized by UV-visible spectroscopy, X-ray diffractometer, Scherrer’s formula, scanning electron microscopy, and FTIR analysis.


Author(s):  
C. Wolpers ◽  
R. Blaschke

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.


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