@article {2663,
	title = {A Carboxy-Terminal Affinity Tag for the Purification and Mass Spectrometric Characterization of Integral Membrane Proteins},
	journal = {Journal of Proteome Research},
	volume = {8},
	number = {5},
	year = {2009},
	note = {ISI Document Delivery No.: 441BWTimes Cited: 3Cited Reference Count: 22Wong, Julie P. Reboul, Emmanuelle Molday, Robert S. Kast, Juergen},
	month = {May},
	pages = {2388-2396},
	type = {Article},
	abstract = {G-protein-coupled receptors (GPCRs) and other structurally and functionally related membrane proteins represent particularly attractive targets for drug discovery. Integral membrane proteins are often difficult to purify from native contexts, and lack of sufficient quantities hampers subsequent structural and functional proteomic studies. We describe here an optimized enrichment strategy involving a membrane protein-compatible 1D4 affinity tag that is derived from the carboxy-terminal nine amino residues of bovine rhodopsin, and its corresponding tag-specific, high-affinity monoclonal antibody. When two GPCRs as well as two related ATP binding cassette (ABC) transporters are expressed in their functional forms in human cell lines, we have shown that a single detergent and wash condition can be employed for the purification of all said membrane proteins. Subsequent in-gel digestion with trypsin and mass spectrometric peptide analysis resulted in high sequence coverage for the ABC transporters ABCA1-1D4 and ABCA4-1D4. In contrast, digestion by various enzymatic combinations was necessary to obtain the best sequence coverage for affinity-enriched GPCRs CXCR4-1D4 and CCR5-1D4 as compared against other entries in an annotated spectrum library. Furthermore, specific enzyme combinations were necessary to produce suitable peptides for deducing N-glycosylation sites on CXCR4. Our results demonstrate that the 1D4-tag enrichment strategy is a versatile tool for the characterization of integral membrane proteins that can be employed for functional proteomic studies.},
	keywords = {1D4 affinity tag, 2-DIMENSIONAL, annotated spectrum libraries, ATP binding cassette transporters, BINDING, ELECTROPHORESIS, EXPRESSION, G-protein-coupled, membrane protein enrichment, N-LINKED GLYCOSYLATION, PROTEOMICS, proteotypic peptides, RECEPTOR, RECEPTORS, RHODOPSIN, ROD OUTER SEGMENTS, SITES, SYNTHETIC PEPTIDES, Tandem mass spectrometry},
	isbn = {1535-3893},
	url = {<Go to ISI>://000265745300025},
	author = {Wong, J. P. and Reboul, E. and Molday, R. S. and Kast, J.}
}
@article {341,
	title = {Accurately describing weak analyte-additive interactions by capillary electrophoresis},
	journal = {Electrophoresis},
	volume = {23},
	number = {6},
	year = {2002},
	note = {ISI Document Delivery No.: 536KNTimes Cited: 12Cited Reference Count: 33},
	month = {Mar},
	pages = {880-888},
	type = {Article},
	abstract = {When modeling analyte-additive interactions in capillary electrophoresis (CE), it is necessary to correct for all changes in the apparent electrophoretic mobility of an analyte that are not due to specific binding. Current models based on dynamic complexation have corrected for bulk viscosity changes in the background electrolyte (BGE) when additives are used, while assuming negligible changes in the dielectric constant and other physicochemical properties of the solution. In this report, a study of weak interactions between deoxyribonucleotides and hydroxypropyl-beta-cyclodextrin (HP-beta-CD) revealed significant nonideality in binding isotherms. Changes in the dielectric properties of the solution due to the addition of high concentrations of HP-beta-CD to the BGE was observed to alter the electrophoretic mobility of analytes. A relative dielectric correction factor was required to normalize analyte mobilities to a reference state of zero additive concentration. The use of both a relative dielectric factor and a viscosity correction factor was found to increase the accuracy of the model, reflected by a higher degree of correlation between predicted and measured analyte mobilities. This type of correction is particularly relevant when studying weak analyte binding interactions or when using high concentrations of additive in the BGE. This work is vital for accurate determination of weak binding constants and mobility values, as well as providing a deeper understanding of the fundamental parameters influencing a separation in CE.},
	keywords = {analyte-additive interactions, BETA-CYCLODEXTRIN, binding isotherms, capillary electrophoresis, CHIRAL SEPARATION, cyclodextrin, deoxyribonucleotides, DYNAMIC COMPLEXATION, ELECTROKINETIC CHROMATOGRAPHY, ELECTROPHORESIS, ENANTIOMERS, MIGRATION BEHAVIOR, MODEL, OPTIMIZATION, QUANTITATIVE DESCRIPTION, viscosity-dielectric corrections factors, weak, ZONE},
	isbn = {0173-0835},
	url = {<Go to ISI>://000174699400008},
	author = {Britz-McKibbin, P. and Chen, D. D. Y.}
}
@article {4920,
	title = {Electrospray ionization of alkali and alkaline earth metal species. Electrochemical oxidation and pH effects},
	journal = {Journal of Mass Spectrometry},
	volume = {35},
	number = {8},
	year = {2000},
	note = {ISI Document Delivery No.: 347MUTimes Cited: 7Cited Reference Count: 49},
	month = {Aug},
	pages = {981-989},
	type = {Article},
	abstract = {The utility of electrospray ionization mass spectrometry (ESI-MS) for characterizing dissolved metal species has generated considerable interest in the use of this technique for metal speciation, However, the development of accurate speciation methods based on ESI-R;IS requires a detailed understanding of the mechanisms by which dissolved metal species are ionized during electrospray. We report how the analysis of alkali and alkaline earth metal species pro,ides new information about some of the processes that affect electrospray ion yield. Selected metal ions and organic ligands were combined in 50:50 water-acetonitrile buffered with acetic acid or ammonium acetate and analyzed by flow injection ESI-MS using mild electrospray conditions. Species formed by alkali metal ions with thiol and oxygen-donating ligands were detected in acidic and neutral pH solutions. Electrochemical oxidation of N,N-diethyldithiocarbamate and glutathione during electrospray was indicated by detection of the corresponding disulfides as protonated or alkali metal species, The extent of ligand oxidation depended on solution pH and the dissociation constant of the thiol group, Tandem mass spectrometric experiments suggested that radical cations such as [NaL](+.) (where L = N,N -diethyldithiocarbamate) can be generated by in-source fragmentation of disulfide species. Greater complexation of alkali metals at neutral pH tvas indicated by a corresponding decrease in the relative abundance of the free metal ion, The number of alkali metal ions bound by glutathione and phthalic acid also increased with increasing pH, in accordance with thermodynamic equilibrium theory. Alkaline earth metal species were detected only in acidic solutions, the absence of 8-hydroxyquinoline complexes being attributed to their relative instability and subsequent dissociation during electrospray, Hence, accurate speciation by ESI-MS depends on experimental conditions and the intrinsic properties of each analyte, Copyright (C) 2000 John Wiley \&; Sons, Ltd.},
	keywords = {cell, COMPLEXES, electrochemical oxidation, ELECTROPHORESIS, electrospray ionization, ION-TRAP, MASS-SPECTROMETRY, metal speciation, OLIGONUCLEOTIDES, PEPTIDES, pH effects, PROTEINS, STOICHIOMETRY, thiol ligands, WATER},
	isbn = {1076-5174},
	url = {<Go to ISI>://000088934400006},
	author = {Ross, A. R. S. and Ikonomou, M. G. and Orians, K. J.}
}
@article {4738,
	title = {Velocity-difference induced focusing of nucleotides in capillary electrophoresis with a dynamic pH junction},
	journal = {Analytical Chemistry},
	volume = {72},
	number = {8},
	year = {2000},
	note = {ISI Document Delivery No.: 304RDTimes Cited: 122Cited Reference Count: 35},
	month = {Apr},
	pages = {1729-1735},
	type = {Article},
	abstract = {Velocity-difference induced focusing (V-DIF) of nucleotides was achieved by using a dynamic pH junction in capillary electrophoresis (CE) with UV detection. The influence of specific analyte properties, such as nucleotide base structure, sugar structure, and degree of phosphorylation, is examined. The pK(a) values and berate complexation with vicinal diols are important factors that caused the focusing. Therefore, the pH and berate content in the sample and background electrolyte can be adjusted to optimize the focusing effect. This method allows the injection of large volumes of sample (similar to 300 nL), resulting in at least 50-fold improvement in concentration sensitivity. The detection limit of 4.0 x 10(-8) M for nucleotides can be achieved in favorable conditions. V-DIF can be also applied to nucleotide pool analysis from cell extracts to improve the concentration sensitivity of CE and to reduce the time-consuming steps of desalting and off-line preconcentration that are often required for assays of nucleotides from biological samples.},
	keywords = {DNA-ADDUCTS, ELECTROPHORESIS, INJECTION, ISOTACHOPHORESIS, MICELLAR ELECTROKINETIC CHROMATOGRAPHY, NEUTRAL ANALYTES, SAMPLE SELF-STACKING, SEPARATION, TRIPHOSPHATES, VOLUME, ZONE},
	isbn = {0003-2700},
	url = {<Go to ISI>://000086497200001},
	author = {Britz-McKibbin, P. and Bebault, G. M. and Chen, D. D. Y.}
}
@article {4206,
	title = {The effect of complexation additives on analyte migration behavior in capillary electrochromatography},
	journal = {Electrophoresis},
	volume = {19},
	number = {8-9},
	year = {1998},
	note = {ISI Document Delivery No.: ZY715Times Cited: 6Cited Reference Count: 22},
	month = {Jun},
	pages = {1452-1460},
	type = {Article},
	abstract = {In capillary electrochromatography (CEC), analytes often have different mobilities in the mobile phase, and often are involved in multiple equilibria. In this paper, the migration behavior of an analyte in CEC is described by a general equation in which individual capacity factors are used to describe the tendency of the analyte to exist as the various analyte species present in a separation system, and the effects of both field and equilibrium are accounted for. The resolution of two analytes is shown to be related linearly to the ratio of their migration rates. The effect of the electroosmotic flow (EOF) in CEC is more complicated than in CE because it is experienced only by a fraction of the analyte, whereas in CE, it is experienced by all analyte species. A procedure for calculating the electrophoretic mobility of the analyte based on the fraction of the analyte in the buffer is demonstrated. The effect of the EOF on resolution is also discussed.},
	keywords = {additives, capillary electrochromatography, COMPLEXATION, ELECTROPHORESIS, LIQUID-CHROMATOGRAPHY, multiple equilibria, PARAMETERS, separation theory, SEPARATIONS},
	isbn = {0173-0835},
	url = {<Go to ISI>://000074652100040},
	author = {Bowser, M. T. and Chen, D. D. Y.}
}
@article {4317,
	title = {The effects of a mixture of charged and neutral additives on analyte migration behavior in capillary electrophoresis},
	journal = {Electrophoresis},
	volume = {19},
	number = {3},
	year = {1998},
	note = {ISI Document Delivery No.: ZD713Times Cited: 14Cited Reference Count: 45},
	month = {Mar},
	pages = {388-396},
	type = {Article},
	abstract = {Multicomponent additives, such as derivatized cyclodextrins with various degrees of substitution, can be considered single-component additives as long as the fraction of each component remains constant. In this paper, equations are derived describing the effect of such additives on the migration behavior of analytes. These equations are used in the study of capillary electrophoresis (CE) systems with differentially charged cyclodextrins as additives. For weakly acidic analytes, the binding with highly negatively charged sulfobutyl ether beta-cyclodextrin (SBE-beta-CD) increases their negative electrophoretic mobility, while the binding with neutral hydroxypropyl-beta-cyclodextrin (HP-beta-CD) decreases their negative mobility. By obtaining the equilibrium constants and mobilities for each additive with each analyte (in this case, phenol, 2-naphthol and 1-naphthol), the migration behavior of these analytes in CE systems is quantitatively predicted at various concentrations of mixtures of the two additives. The properties of the contour lines in the binding isotherm surfaces of such CE systems are discussed.},
	keywords = {ANALYTE, ASPECTS, BETA-CYCLODEXTRIN, CHIRAL, ELECTROPHORESIS, MICELLAR ELECTROKINETIC CHROMATOGRAPHY, MIGRATION BEHAVIOR, MOBILE PHASES, multicomponent additives, RESOLUTION, SELECTIVITY, SEPARATION, separation theory, STATIONARY PHASE, THEORETICAL, TIOCONAZOLE ENANTIOMERS, two-additive capillary, ZONE ELECTROPHORESIS},
	isbn = {0173-0835},
	url = {<Go to ISI>://000072716000004},
	author = {Kranack, A. R. and Bowser, M. T. and Britz-McKibbin, P. and Chen, D. D. Y.}
}
@article {3763,
	title = {Driving forces for DNA adsorption to silica in perchlorate solutions},
	journal = {Journal of Colloid and Interface Science},
	volume = {181},
	number = {2},
	year = {1996},
	note = {ISI Document Delivery No.: UZ536Times Cited: 112Cited Reference Count: 43},
	month = {Aug},
	pages = {635-644},
	type = {Article},
	abstract = {The adsorption of both plasmid and chromosomal duplex DNA to silica is investigated with the aim of determining the dominant forces involved in the binding reaction. Changes in the initial slopes and plateau values of adsorption isotherms for DNA on microcrystalline silica particles are used to establish the sensitivity of the binding reaction to ionic strength, temperature and pH, and DNA size and conformation. Binding is driven by an increase in entropy, with little or no enthalpic contribution. Adsorption isotherm results indicate that three effects, namely: (i) shielded intermolecular electrostatic forces, (ii) dehydration of the DNA and silica surfaces, and (iii) intermolecular hydrogen bond formation in the DNA-silica contact layer, make the dominant contributions to the overall driving force for adsorption. (C) 1996 Academic Press, Inc.},
	keywords = {adsorption isotherms, ARRAYS, CHIPS, CONFORMATION, DNA, DNA adsorption, DNA binding, DNA PURIFICATION, DNA-silica interactions, ELECTROPHORESIS, GLOBULAR-PROTEINS, PLASMID DNA, PURIFICATION, SURFACES, TRANSITION},
	isbn = {0021-9797},
	url = {<Go to ISI>://A1996UZ53600031},
	author = {Melzak, K. A. and Sherwood, C. S. and Turner, R. F. B. and Haynes, C. A.}
}
