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1.
M. Y. Shukor M. F. Rahman Z. Suhaili N. A. Shamaan M. A. Syed 《World journal of microbiology & biotechnology》2009,25(7):1225-1234
A bacterium that was able to tolerate and reduce as high as 50 mM of sodium molybdate to molybdenum blue has been isolated
from a metal recycling ground. The isolate was tentatively identified as Serratia sp. strain Dr.Y8 based on the carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny.
ANOVA analysis showed that isolate Dr.Y8 produced significantly higher (P < 0.05) amount of Mo-blue with 3, 5.1 and 11.3 times more molybdenum blue than previously isolated molybdenum reducers such
as Serratia
marcescens strain Dr.Y6, E. coli K12 and E. cloacae strain 48, respectively. Its molybdate reduction characteristics were studied in this work. Electron donor sources such as
sucrose, mannitol, fructose, glucose and starch supported molybdate reduction. The optimum phosphate, pH and temperature that
supported molybdate reduction were 5 mM, pH 6.0 and 37°C, respectively. The molybdenum blue produced from cellular reduction
exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium,
silver, copper and mercury resulted in approximately 61, 57, 80, and 69% inhibition of the molybdenum-reducing activity at
1 mM, respectively. The reduction characteristics of strain Dr.Y8 suggest that it would be useful in future molybdenum bioremediation. 相似文献
2.
Perspective texture synthesis has great significance in many fields like video editing, scene capturing etc., due to its ability to read and control global feature information. In this paper, we present a novel example-based, specifically energy optimization-based algorithm, to synthesize perspective textures. Energy optimization technique is a pixel-based approach, so it’s time-consuming. We improve it from two aspects with the purpose of achieving faster synthesis and high quality. Firstly, we change this pixel-based technique by replacing the pixel computation with a little patch. Secondly, we present a novel technique to accelerate searching nearest neighborhoods in energy optimization. Using k- means clustering technique to build a search tree to accelerate the search. Hence, we make use of principal component analysis (PCA) technique to reduce dimensions of input vectors. The high quality results prove that our approach is feasible. Besides, our proposed algorithm needs shorter time relative to other similar methods. 相似文献
3.
Julia I. Gavrilyuk Ulrich Wuellner Syed Salahuddin Rajib K. Goswami Subhash C. Sinha Carlos F. Barbas 《Bioorganic & medicinal chemistry letters》2009,19(14):3716-3720
Irreversible chemical programming of monoclonal aldolase antibody (mAb) 38C2 has been accomplished with β-lactam equipped mono- and bifunctional targeting modules, including a cyclic-RGD peptide linked to either the peptide (d-Lys6)-LHRH or another cyclic RGD unit and a small-molecule integrin inhibitor SCS-873 conjugated to (d-Lys6)LHRH. We also prepared monofunctional targeting modules containing either cyclic RGD or (d-Lys6)-LHRH peptides. Binding of the chemically programmed antibodies to integrin receptors α(v)β(3) and α(v)β(5) and to the luteinizing hormone releasing hormone receptor were evaluated. The bifunctional and bivalent c-RGD/LHRH and SCS-783/LHRH, the monofunctional and tetravalent c-RGD/c-RGD, and the monofunctional bivalent c-RGD chemically programmed antibodies bound specifically to the isolated integrin receptor proteins as well as to integrins expressed on human melanoma M-21 cells. c-RGD/LHRH, SCS-783/LHRH, and LHRH chemically programmed antibodies bound specifically to the LHRH receptors expressed on human ovarian cancer cells. This approach provides an efficient, versatile, and economically viable route to high-valency therapeutic antibodies that target defined combinations of specific receptors. Additionally, this approach should be applicable to chemically programmed vaccines. 相似文献
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5.
The complete primary structure of the two hemoglobin components of the Great Indian Rhinoceros (Rhinoceros unicornis) is presented. The ratio for the two components B(alpha 2 beta I2): A(alpha 2 beta II2) is 6:4. Polypeptide subunits were separated by chromatography on CM-cellulose in a buffer containing 8M urea. The sequence was studied by degradation of the tryptic and hydrolytic cleavage products in a liquid phase sequencer. At position beta NA2 component B has Asp, whereas component A has Glu, an ATP-binding site in fish and reptilian hemoglobins. The other phosphate binding sites i.e. beta NA1 Val, beta EF6 Lys and beta H21 His are identical with 2,3-bisphosphoglycerate-(DPG)binding sites in mammalian hemoglobins, whereby rhinoceros hemoglobin resembles both ATP-sensitive poikilotherm hemoglobin and DPG-sensitive mammalian hemoglobin. The two components (beta I/beta II) additionally differ by exchange of Glu----Gly at position beta A3 and Gln----Lys at position beta GH3. The significance of these changes is discussed. Oxygenation properties of the two hemoglobins components and their dependence on ATP and DPG are given. The structure and function of Rhinoceros hemoglobin may give an insight into the evolution of the organic phosphate binding in vertebrate hemoglobins. 相似文献
6.
The complete amino acid sequence of the major component of hemoglobin from amur-leopard (Panthera pardus orientalis) is presented. The major component accounts for more than 90% of the total hemoglobin. Separation of the globin subunits was achieved by ion-exchange chromatography on CM-cellulose in urea. The sequence was studied by automatic Edman degradation of tryptic and hydrolytic peptides. Alignment was carried out with human hemoglobin sequence. The NH2 terminus is blocked with Ac-serine. The data are compared with other mammalian hemoglobins and results are discussed with respect to sequence and physiology.85th communication on hemoglobin. 相似文献
7.
A highly specific proteolytic enzyme cleaving at the carboxyl group of valine has been isolated from Candida tropicalis. Its specificity has been determined by digesting beta-lactoglobulin and a number of synthetic peptides. The enzyme a glycoprotein, has a molecular mass of 40 +/- 7 kDa on the basis of sodium dodecyl sulphate polyacrylamide gel electrophoresis. Its optimum activity occurs at 37 degrees C at a pH between 8-9. It has been named "Valyl-proteinase" because of its selective cleavage. 相似文献
8.
Xanthomonas campestris pv. glycines , (Xcg), the causative agent of the bacterial pustule disease of soybean was isolated and characterized. On susceptible soybean the pathogenic isolates displayed characteristic chlorotic lesions around the site of infection within 48 h of inoculation. The pathogenic isolates were found to contain two cryptic plasmids. A smaller plasmid of 1.5 kb and a larger one of size about 25 kb. SDS-PAGE profile of the soluble proteins of the pathogenic isolatess, howed a different pattern compared to that of the non-pathogenic isolates. 相似文献
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10.
Shafiq Fahad Iqbal Muhammad Raza Syed Hammad Akram Nudrat Aisha Ashraf Muhammad 《Journal of Plant Growth Regulation》2023,42(3):1267-1290
Journal of Plant Growth Regulation - Fullerenols are carbon nanoparticles that have been declared as free radical sponges. There is a need to take a prudent path toward its applications in various... 相似文献