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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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6.
Demet Tademir Ayegül Karaküük‐yidoan Mustafa Ulali Tuba Takin‐Tok Emne Eln Oru‐Emre Hasan Bayram 《Chirality》2015,27(2):177-188
A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF‐7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC‐27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound 17b exhibited the most potent activity (IC50 4.6 μM) against HGC‐27 as compared with the reference compound, sindaxel (IC50 10.3 μM), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177–188, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
7.
Dr. Kauko K. Mäkinen Eva Söderling Salam A. Syed Pirkko-Liisa Mäkinen 《Current microbiology》1990,20(1):5-11
The cell extracts of two human oral strains (FN2 and FN3) ofFusobacterium nucleatum displayed exceptionally high-glutamylpeptidase activity as determined withN--l-glutamyl-2-naphthylamine as substrate. This activity was so dominant that the hydrolysis of otherN-aminoacyl-2-naphthylamines progressed at a rate <10% of the former. Two major enzymes (I and II) were partially purified from FN2. I had a molecular weight of 115,000 and did not hydrolyze-glutamylcysteinylglycine (glutathione). II had a molecular weight of 70,000 and rapidly liberated only glutamic acid from glutathione. Strain FN3 contained several enzymes hydrolyzing-glu-2NA. Direct anion exchange chromatography of FN3 cell extracts separated one enzyme that liberated both glutamic acid and glycine from glutathione, one that was inactive against glutathione (but hydrolyzed-glu-2NA), and one that liberated only glutamic acid. Although-glu-2NA was a good synthetic substrate, glutathione was hydrolyzed at least 500 times faster by an enzyme present in both strains. These results indicate that the presence of-glutamylpeptidase activity is very characteristic of theseF. nucleatum strains. 相似文献
8.
Autonomous DNA binding domains of lambda integrase recognize two different sequence families 总被引:35,自引:0,他引:35
The 40 kd lambda Integrase protein is shown to contain two autonomous DNA binding domains with different sequence specificities. Competition experiments in which the binding activity of Int is assayed through nuclease protection demonstrate the functional independence of the two DNA recognition specificities. Proteolytic cleavage of Int and footprinting analysis of the resulting two major peptides allow the physical separation and identification of two DNA binding domains: an amino-terminal peptide that interacts with "arm-type" sites and a carboxy-terminal peptide that binds to "core-type" sequences. In addition, the data suggest that the two domains can bind DNA simultaneously, consistent with a model in which Integrase would link two disparate DNA sequences. 相似文献
9.
Summary Snake flask experiments were carried out as a preliminary study of fat formation byTrichoderma
reesei (formallyviride) QM 9123 using a glucose based medium. The maximum quantity of fat production was 16% of the dry weight. The pH of the medium, as much as its composition, appeared to influence the quantity of fat that was produced. The fatty acids formed by the hydrolysis of the fats were found to be mainly unsaturated, with the 182 (linoleic) acid predominating. 相似文献
10.
S. I. Hasan Barbara A. D. Blaney J. L. Turk 《Cancer immunology, immunotherapy : CII》1992,34(4):228-232
Summary This study investigates the effects of anticancer drugs and immunomodulating agents on the release of interleukin-6 (IL-6) from lipopolysaccharide-stimulated human peripheral blood mononuclear leucocytes in vitro. The addition of non-cytotoxic concentrations of Adriamycin (doxorubicin), vincristine and 4-OOH-cyclophosphamide (the in vitro active analogue of cyclophosphamide) resulted in suppression of IL-6 release. The drugs bleomycin, FK156 [d-lactoyl-l-alanyl--d-glutamyl-(l)-meso-diaminopimelyl-(l)-glycine], FK565 [heptanoyl--d-glutamyl-(l)-meso-diaminopimelyl-(d)-alanine] and the immunosuppressive agent cyclosporin A did not alter the release of IL-6 in the same experimental system. 相似文献