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51.
Koch Rainer Lipton Andrew S. Filipek Slawomir Renugopalakrishnan Venkatesan 《Journal of molecular modeling》2011,17(6):1467-1472
Density functional theoretical calculations have been utilized to investigate the interaction of the amino acid arginine with
the (100) surface of anatase and the reproduction of experimentally measured 49Ti NMR chemical shifts of anatase. Significant binding of arginine through electrostatic interaction and hydrogen bonds of
the arginine guanidinium protons to the TiO2 surface oxygen atoms is observed, allowing attachment of proteins to titania surfaces in the construction of bio-sensitized
solar cells. GIAO-B3LYP/6-31G(d) NMR calculation of a three-layer model based on the experimental structure of this TiO2 modification gives an excellent reproduction of the experimental value (-927 ppm) within +/- 7 ppm, however, the change in
relative chemical shifts, EFGs and CSA suggest that the effect of the electrostatic arginine binding might be too small for
experimental detection. 相似文献
52.
Kanmani P Kumar RS Yuvaraj N Paari KA Pattukumar V Arul V 《Preparative biochemistry & biotechnology》2011,41(1):40-52
Statistics-based experimental designs were used to develop a cost-effective medium for enhanced production of viable cells and bacteriocin by probiotic Enterococcus faecium MC13. Carbon, nitrogen, and mineral sources were first screened by one-variable-at-a-time (OVAT) methods. In order to increase yield production, the selected variables were further statistically optimized using response-surface methodology (RSM) with central composite design (CCD). The maximum and minimum levels of the selected variables were determined and a set of 34 experimental runs was performed. The optimum concentrations of the tested variables for production of viable cells (12.24 log CFU mL(-1)) and bacteriocin activity (25,600 AU mL(-1)) were tryptone (10.0 g/L), peptone (6.0 g/L), maltose (3.0 g/L), glucose (9.0 g/L), NaCl (15.0 g/L), sodium citrate (2.5 g/L), sodium acetate (1.0 g/L), and dipotassium PO(4) (0.1 g/L). Threefold increased yield of bacteriocin was achieved in optimized medium compared to the unoptimized counterpart, and this was two times less cost than commercial MRS medium. 相似文献
53.
Vijayabharathi R Bruheim P Andreassen T Raja DS Devi PB Sathyabama S Priyadarisini VB 《Journal of microbiology (Seoul, Korea)》2011,49(6):920-926
A new actinomycete strain, isolated from humus soils in the Western Ghats, was found to be an efficient pigment producer.
The strain, designated AAA5, was identified as a putative Streptomyces aurantiacus strain based on cultural properties, morphology, carbon source utilization, and analysis of the 16S rRNA gene. The strain
produced a reddish-brown pigmented compound during the secondary metabolites phase. A yellow compound was derived from the
extracted pigment and was identified as the quinone-related antibiotic resistomycin based on ultraviolet-visible spectrophotometry,
fourier transform infrared spectroscopy, liquid chromatography and mass spectroscopy, and nuclear magnetic resonance analyses.
The AAA5 strain was found to produce large quantities of resistomycin (52.5 mg/L). It showed potent cytotoxic activity against
cell lines viz. HepG2 (hepatic carcinoma) and HeLa (cervical carcinoma) in vitro, with growth inhibition (GI50) of 0.006 and 0.005 μg/ml, respectively. The strain also exhibited broad antimicrobial activities against both Gram-positive
and Gram-negative bacteria. Therefore, AAA5 may have great potential as an industrial resistomycin-producing strain. 相似文献
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55.
Thachamvally Riyesh Vinayagamurthy Balamurugan Arnab Sen Veerakyathappa Bhanuprakash Gnanavel Venkatesan Vinita Yadav Raj Kumar Singh 《中国病毒学》2011,26(5):324-337
In this study, thermo-adapted (Ta) PPR vaccines were assessed for their stability at 25, 37, 40, 42 and 45°C in lyophilized
form using two extrinsic stabilizers {lactalbumin hydrolysate-sucrose (LS) and stabilizer E} and in reconstituted form with
the diluents (1 mol/L MgSO4 or 0.85% NaCl). The lyophilized vaccines showed an expiry period of 24–26 days at 25°C, 7–8 days at 37°C and 3–4 days at
40°C. LS stabilizer was superior at 42°C with a shelf-life of 44 h, whereas in stabilizer E, a 40 h shelf-life with a comparable
half-life was observed. At 45°C, the half-life in stabilizer E was better than LS and lasted for 1 day. Furthermore, the reconstituted
vaccine maintained the titre for 48 h both at 4°C and 25°C and for 24–30 h at 37°C. As both the stabilizers performed equally
well with regard to shelf-life and half-life, the present study suggests LS as stabilizer as a choice for lyophilization with
0.85% NaCl diluent, because it has better performance at higher temperature. These Ta vaccines can be used as alternatives
to existing vaccines for the control of the disease in tropical countries as they are effective in avoiding vaccination failure
due to the breakdown in cold-chain maintenance, as this vaccine is considerably more stable at ambient temperatures. 相似文献
56.
Diagnosis of triple negative breast cancer using expression data with several machine learning tools
Breast cancer is one of the top three commonly caused cancers worldwide. Triple Negative Breast Cancer (TNBC), a subtype of breast cancer, lacks expression of the oestrogen receptor, progesterone receptor, and HER2. This makes the prognosis poor and early detection hard. Therefore, AI based neural models such as Binary Logistic Regression, Multi-Layer Perceptron and Radial Basis Functions were used for differential diagnosis of normal samples and TNBC samples collected from signal intensity data of microarray experiment. Genes that were significantly upregulated in TNBC were compared with healthy controls. The MLP model classified TNBC and normal cells with anaccuracy of 93.4%. However, RBF gave 74% accuracy and binary Logistic Regression model showed an accuracy of 90.0% in identifying TNBC cases. 相似文献
57.
Human parainfluenza type 3 virus hemagglutinin-neuraminidase glycoprotein: nucleotide sequence of mRNA and limited amino acid sequence of the purified protein. 总被引:5,自引:10,他引:5 下载免费PDF全文
The nucleotide sequence of mRNA for the hemagglutinin-neuraminidase (HN) protein of human parainfluenza type 3 virus obtained from the corresponding cDNA clone had a single long open reading frame encoding a putative protein of 64,254 daltons consisting of 572 amino acids. The deduced protein sequence was confirmed by limited N-terminal amino acid microsequencing of CNBr cleavage fragments of native HN that was purified by immunoprecipitation. The HN protein is moderately hydrophobic and has four potential sites (Asn-X-Ser/Thr) of N-glycosylation in the C-terminal half of the molecule. It is devoid of both the N-terminal signal sequence and the C-terminal membrane anchorage domain characteristic of the hemagglutinin of influenza virus and the fusion (F0) protein of the paramyxoviruses. Instead, it has a single prominent hydrophobic region capable of membrane insertion beginning at 32 residues from the N terminus. This N-terminal membrane insertion is similar to that of influenza virus neuraminidase and the recently reported structures of HN proteins of Sendai virus and simian virus 5. 相似文献
58.
Anas A Paul S Jayaprakash NS Philip R Bright Singh IS 《Diseases of aquatic organisms》2005,67(1-2):177-179
Chitosan is a biocompatible and biodegradable natural polymer with established antimicrobial properties against specific microorganisms. The present study demonstrates its antibacterial activity against 48 isolates of Vibrio species from prawn larval rearing systems. The antibacterial activity had a positive correlation with the concentration of chitosan. This work opens up avenues for using chitosan as a prophylactic biopolymer for protecting prawn larvae from vibriosis. 相似文献
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