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Author Gajer, P.; Brotman, R.M.; Bai, G.; Sakamoto, J.; Schutte, U.M.E.; Zhong, X.; Koenig, S.S.K.; Fu, L.; Ma, Z.S.; Zhou, X.; Abdo, Z.; Forney, L.J.; Ravel, J. file  url
Title Temporal dynamics of the human vaginal microbiota Type Journal Article
Year 2012 Publication Science Translational Medicine Abbreviated Journal Sci Transl Med  
Volume 4 Issue 132 Pages 132ra52  
Keywords Bacteria/classification/genetics; Female; Humans; Magnetic Resonance Spectroscopy; Metabolome; Metabolomics; Metagenome/genetics/*physiology; Models, Biological; Phylogeny; Time Factors; Vagina/*microbiology; Microbiome  
Abstract Elucidating the factors that impinge on the stability of bacterial communities in the vagina may help in predicting the risk of diseases that affect women's health. Here, we describe the temporal dynamics of the composition of vaginal bacterial communities in 32 reproductive-age women over a 16-week period. The analysis revealed the dynamics of five major classes of bacterial communities and showed that some communities change markedly over short time periods, whereas others are relatively stable. Modeling community stability using new quantitative measures indicates that deviation from stability correlates with time in the menstrual cycle, bacterial community composition, and sexual activity. The women studied are healthy; thus, it appears that neither variation in community composition per se nor higher levels of observed diversity (co-dominance) are necessarily indicative of dysbiosis.  
Call Number Serial 2175  
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Author Privalov, P.L.; Griko YuV; Venyaminov SYu; Kutyshenko, V.P. file  url
Title Cold denaturation of myoglobin Type Journal Article
Year 1986 Publication Journal of Molecular Biology Abbreviated Journal J Mol Biol  
Volume 190 Issue 3 Pages 487-498  
Keywords Animals; Calorimetry; *Cetacea; *Cold Temperature; *Hemeproteins; Hydrogen-Ion Concentration; Magnetic Resonance Spectroscopy; *Metmyoglobin; Protein Denaturation; Spectrum Analysis; Temperature; Thermodynamics; *Whales  
Abstract The stability of the structure of sperm whale metmyoglobin has been studied in various solutions, in the temperature range -8 degrees C to 100 degrees C, by scanning microcalorimetry, light absorption, circular dichroism, nuclear magnetic resonance spectroscopy and viscosimetry. It has been shown that in 10 mM-sodium acetate solutions (pH 3.5 to 3.9) the protein molecule undergoes a reversible conformational transition into a non-compact disordered state not only when the solution is heated above room temperature but also when it is cooled. In this state the protein does not have a tertiary structure, although it retains some residual ellipticity, which may be caused by the fluctuating alpha-helical conformation of the unfolded polypeptide chain. The disruption of the native protein structure both on cooling (cold-denaturation) and on heating (heat-denaturation) proceeds in an “all-or-none” manner, with a significant and similar increase of the protein heat capacity, but with inverse enthalpic and entropic effects: the enthalpy and entropy of the protein molecule decrease during cold-denaturation and increase during heat-denaturation.  
Call Number Serial 1564  
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Author Dingley, A.J.; Lorenzen, I.; Grotzinger, J. file  url
Title NMR analysis of viral protein structures Type Journal Article
Year 2008 Publication Methods in Molecular Biology (Clifton, N.J.) Abbreviated Journal Methods Mol Biol  
Volume 451 Issue Pages 441-462  
Keywords Cloning, Molecular; DNA, Complementary; Indicators and Reagents; Magnetic Resonance Spectroscopy--methods; Models, Molecular; Protein Conformation; Recombinant Proteins--chemistry; Solutions; Viral Proteins--chemistry, genetics, isolation & purification  
Abstract Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool to study the three-dimensional structure of proteins and nucleic acids at atomic resolution. Since the NMR data can be recorded in solution, conditions such as pH, salt concentration, and temperature can be adjusted so as to closely mimic the biomacromolecules natural milieu. In addition to structure determination, NMR applications can investigate time-dependent phenomena, such as dynamic features of the biomacromolecules, reaction kinetics, molecular recognition, or protein folding. The advent of higher magnetic field strengths, new technical developments, and the use of either uniform or selective isotopic labeling techniques, currently allows NMR users the opportunity to investigate the tertiary structure of biomacromolecules of approximately 50 kDa. This chapter will outline the basic protocol for structure determination of proteins by NMR spectroscopy. In general, there are four main stages: (i) preparation of a homogeneous protein sample, (ii) the recording of the NMR data sets, (iii) assignment of the spectra to each NMR observable atom in the protein, and (iv) generation of structures using computer software and the correctly assigned NMR data.  
Call Number Serial 782  
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Author Tsikolia, M.; Hall, A.C.; Suarez, C.; Nylander, Z.O.; Wardlaw, S.M.; Gibson, M.E.; Valentine, K.L.; Onyewadume, L.N.; Ahove, D.A.; Woodbury, M.; Mongare, M.M.; Hall, C.D.; Wang, Z.; Draghici, B.; Katritzky, A.R. file  url
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Title Synthesis and characterization of a redox-active ion channel supporting cation flux in lipid bilayers Type Journal Article
Year 2009 Publication Organic & Biomolecular Chemistry Abbreviated Journal Org Biomol Chem  
Volume 7 Issue 18 Pages 3862-3870  
Keywords Biological Transport; Cations/*metabolism; Cell Membrane/chemistry/metabolism; Electric Conductivity; Ferrous Compounds/chemistry; Ion Channels/*chemical synthesis/chemistry/*metabolism; Lipid Bilayers/chemistry/*metabolism; Magnetic Resonance Spectroscopy; Oxidation-Reduction; Spectrometry, Fluorescence  
Abstract The synthesis, cation binding and transmembrane conductive properties of a novel synthetic ion channel containing a redox-active ferrocene unit are described. Fluorescence spectroscopy was used to demonstrate that the channel supports multiple ion coordination and association constants for 1:1 and 1:2 (channel:cation) coordination for both Na(+) and K(+) were evaluated. Experiments using a black lipid membrane preparation revealed that this compound functioned effectively as an ion channel for both Na(+) and K(+). Concomitant (23)Na NMR spectroscopy studies supported this finding and revealed a Na(+) flux, at least 5 times higher than ion transport rates by monensin. Furthermore, oxidation of the redox-active centre (Fe(2+) to Fe(3+)) effectively inhibited ion transport.  
Call Number Serial 511  
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Author Hall, A.C.; Suarez, C.; Hom-Choudhury, A.; Manu, A.N.; Hall, C.D.; Kirkovits, G.J.; Ghiriviga, I. file  url
Title Cation transport by a redox-active synthetic ion channel Type Journal Article
Year 2003 Publication Organic & Biomolecular Chemistry Abbreviated Journal Org Biomol Chem  
Volume 1 Issue 16 Pages 2973-2982  
Keywords Cations; Electrochemistry/methods; Ferrous Compounds/*chemistry; Ion Channels/chemical synthesis/*chemistry; Ion Transport; Kinetics; Lipid Bilayers/*chemistry; Magnetic Resonance Spectroscopy/methods; Oxidation-Reduction; Phosphatidylethanolamines/chemistry; Sodium/chemistry/metabolism; Spectrometry, Fluorescence  
Abstract The synthesis, cation binding and transmembrane conductive properties of a novel group of synthetic ion channels containing a redox-active centre are described. Experiments using a black lipid membrane preparation revealed that these compounds function effectively as ion channels. Subsequent 23Na NMR spectroscopy studies focused on a synthesized ion channel with a ferrocene centre. When incorporated in vesicular bilayers, this channel was demonstrated to support a Na+ flux that was at least six times faster than ion transport by monensin. Since oxidation of the ferrocene moiety completely inhibited the Na+ transport, the redox-active centre provides a potential mechanism for controlling ion flux.  
Call Number Serial 512  
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