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171.
2'-Deoxynucleoside diphosphates and triphosphates were synthesized from 2'-deoxy-nucleoside monophosphates by using nucleoside monophosphate kinase and nucleoside diphosphate kinase enzymes. This biocatalytic procedure is superior to chemical methods for obtaining these compounds and can be extended to other applications. © Rapid Science Ltd. 1998 相似文献
172.
Development and evaluation of a multiplex PCR assay for rapid detection of toxigenic Vibrio cholerae O1 and O139 总被引:7,自引:0,他引:7
173.
James McNulty Jerald J. Nair Jessamyn R.L. Little John D. Brennan Jaume Bastida 《Bioorganic & medicinal chemistry letters》2010,20(17):5290-5294
The synthesis of differentially functionalized analogs of the Amaryllidaceae alkaloid lycorine, accessed via a concise chemoselective silylation strategy, is described uncovering two of the most potent inhibitors of acetylcholinesterase (AChE) identified to date in this series. Important elements of this novel pharmacophore were elucidated through structure–activity relationship (SAR) studies. 相似文献
174.
Jong Yul Roh Manoj S. Nair Xinyan Sylvia Liu & Donald H. Dean 《FEMS microbiology letters》2009,295(2):156-163
The growing resistance against antibiotics demands the search for alternative treatment strategies. Photodynamic therapy is a promising candidate. The natural intermediate of chlorophyll biosynthesis, protochlorophyllide, was produced, purified and tested as a novel photosensitizer for the inactivation of five model organisms including Staphylococcus aureus, Listeria monocytogenes and Yersinia pseudotuberculosis , all responsible for serious clinical infections. When microorganisms were exposed to white light from a tungsten filament lamp (0.1 mW cm−2 ), Gram-positive S. aureus, L. monocytogenes and Bacillus subtilis were photochemically inactivated at concentrations of 0.5 mg L−1 protochlorophyllide. Transmission electron microscopy revealed a disordered septum formation during cell division and the partial loss of the cytoplasmic cell contents. Gram-negative Y. pseudotuberculosis and Escherichia coli were found to be insensitive to protochlorophyllide treatment due to the permeability barrier of the outer membrane. However, the two bacteria were rendered susceptible to eradication by protochlorophyllide (10 mg L−1 ) upon addition of polymyxin B nonapeptide at 50 and 20 mg L−1 , respectively. The release of DNA and a detrimental rearrangement of the cytoplasm were observed. 相似文献
175.
Vipin Thomas Navya Raj Deepthi Varughese Naveen Kumar Seema Sehrawat Abhinav Grover Shailja Singh Pawan K. Dhar Achuthsankar S. Nair 《Systems and synthetic biology》2015,9(4):135-140
Expression of synthetic proteins from intergenic regions of E. coli and their functional association was recently demonstrated (Dhar et al. in J Biol Eng 3:2, 2009. doi:10.1186/1754-1611-3-2). This gave birth to the question: if one can make ‘user-defined’ genes from non-coding genome—how big is the artificially translatable genome? (Dinger et al. in PLoS Comput Biol 4, 2008; Frith et al. in RNA Biol 3(1):40–48, 2006a; Frith et al. in PLoS Genet 2(4):e52, 2006b). To answer this question, we performed a bioinformatics study of all reported E. coli intergenic sequences, in search of novel peptides and proteins, unexpressed by nature. Overall, 2500 E. coli intergenic sequences were computationally translated into ‘protein sequence equivalents’ and matched against all known proteins. Sequences that did not show any resemblance were used for building a comprehensive profile in terms of their structure, function, localization, interactions, stability so on. A total of 362 protein sequences showed evidence of stable tertiary conformations encoded by the intergenic sequences of E. coli genome. Experimental studies are underway to confirm some of the key predictions. This study points to a vast untapped repository of functional molecules lying undiscovered in the non-expressed genome of various organisms. 相似文献
176.
Unusual trend in the prevalence of trisomy 13 in mothers aged 35 and older: A population based study of national congenital anomaly data
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177.
178.
Krishnan Kottekkatu Padinchati Sinha Rupesh Kumar Nair Shanta Noronha Sharon Bibiana Chacko Racheal Anilkumar Narayanapillai 《Annals of microbiology》2015,65(2):1027-1036
Bacterial production, respiration and metabolic diversity were measured up to 120 m depth in the Sub-Antarctic Front (SAF) and Polar Fronts I and II (PFI and PFII) of the Indian Ocean sector of the Southern Ocean during 2010 Austral Summer. Prokaryotic cell count was maximum at PFI and PFII (~109 cells L−1) and minimum at SAF (~107 cells L−1). Furthermore, integrated bacterial production was higher at PFI (1.07 mg C m−2 h−1) and PFII (0.72 mg C m−2 h−1) compared to SAF (0.61 mg C m−2 h−1). At PFII, integrated bacterial growth efficiency was higher (8.96) compared to PFI (7.42) and SAF (7.17), signifying that the net contribution of PFII to the microbial loop could be relatively pronounced. Enhanced cell numbers and production at polar fronts indicate that the dissolved organic matter could be converted to secondary biomass through the microbial loop. However, integrated bacterial respiration rate at PFII (0.83 mg C m−2 h−1) was lower than that at PFI (1.84 mg C m−2 h−1) resulting in higher growth efficiency at PFII. Metabolic flexibility at SAF was clearly brought about by utilization of carboxylic acids like D-malic acid and itaconic acid, and carbohydrates like N-acetyl D-glucosamine, D-cellobiose and D-lactose. Utilization of amino acids like glycyl L-glutamic acid and L-threonine, and an amine, phenylethylamine, was critical in determining the metabolic variability at PFI. PFII hosted microbes that utilized phenolic compounds (2-hydroxy benzoic acid and 4-hydroxy benzoic acid) and polymers (like Tween 80). Utilization of polyols over carbohydrates in polar waters indicates a niche with lesser influence of the Antarctic melt waters on the bacterioplankton metabolism. 相似文献
179.
Manoj S. Nair Marianne M. Lee Astrid Bonnegarde-Bernard Julie A. Wallace Donald H. Dean Michael C. Ostrowski Richard W. Burry Prosper N. Boyaka Michael K. Chan 《PloS one》2015,10(6)
Protein delivery platforms are important tools in the development of novel protein therapeutics and biotechnologies. We have developed a new class of protein delivery agent based on sub-micrometer-sized Cry3Aa protein crystals that naturally form within the bacterium Bacillus thuringiensis. We demonstrate that fusion of the cry3Aa gene to that of various reporter proteins allows for the facile production of Cry3Aa fusion protein crystals for use in subsequent applications. These Cry3Aa fusion protein crystals are efficiently taken up and retained by macrophages and other cell lines in vitro, and can be delivered to mice in vivo via multiple modes of administration. Oral delivery of Cry3Aa fusion protein crystals to C57BL/6 mice leads to their uptake by MHC class II cells, including macrophages in the Peyer’s patches, supporting the notion that the Cry3Aa framework can be used to stabilize cargo protein against degradation for delivery to gastrointestinal lymphoid tissues. 相似文献
180.
Asha Nair Manuela Simonetti Elsa Fabbretti Andrea Nistri 《Cellular and molecular neurobiology》2010,30(4):505-509
Cdk5 is an endogenous kinase activated by the neuronal-specific protein p35 and implicated in multiple neuronal functions,
including modulation of certain pain responses. We investigated whether Cdk5 could regulate ATP-gated P2X3 receptors that are members of the family of membrane proteins expressed by sensory neurons to transduce nociception in baseline
and chronic pain. To study the potential P2X3 receptor modulation by Cdk5, we co-transfected rat P2X3 receptors and Cdk5 into HEK cells and observed increased P2X3 receptor serine phosphorylation together with downregulation of receptor currents only when these genes were transfected
together with the gene of the Cdk5 activator p35. The changes in receptor responses were limited to depressed current amplitude
as desensitization and recovery were not altered. Transfection of p35 with P2X3 similarly downregulated receptor responses, suggesting that this phenomenon could be observed even with constitutive Cdk5.
The present data indicate a novel target to express the action of Cdk5 on membrane proteins involved in pain perception. 相似文献