Este trabajo fue financiado por los Institutos Nacionales de Salud de subvención GM086822 y la Fundación Nacional de Ciencias de investigación importante la instrumentación de subvención DBI-0960313. Los autores desean agradecer a los Dres. Jon Miyake &amp; Donna Hardy (Bio-Rad) y Jennifer Loertscher (Universidad de Seattle), por su experiencia técnica. Seleccione los reactivos y la instrumentación de cromatografía suplementario fueron generosamente proporcionadas por Bio-Rad.

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	<li>Cummins, P. M., O'Connor, B. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrophobic+interaction+chromatography.">Hydrophobic interaction chromatography.</a> Methods Mol. Biol. 681, 431-437 (2011).</li><li>Nagrath, D., Xia, F., Cramer, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+and+modeling+of+nonlinear+hydrophobic+interaction+chromatographic+systems.">Characterization and modeling of nonlinear hydrophobic interaction chromatographic systems.</a> J. Chromatogr. A. 1218, 1219-1226 (2011).</li><li>To, B. C., Lenhoff, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrophobic+interaction+chromatography+of+proteins.+IV.+Protein+adsorption+capacity+and+transport+in+preparative+mode.">Hydrophobic interaction chromatography of proteins. IV. Protein adsorption capacity and transport in preparative mode.</a> J. Chromatogr. A. 1218, 427-440 (2011).</li><li>Huddleston, J. G., Wang, R., Lyddiatt, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+use+of+mild+hydrophobic+interaction+chromatography+for+"method+scouting"+protein+purification+strategies+in+aqueous+two-phase+systems:+a+study+using+model+proteins.">On the use of mild hydrophobic interaction chromatography for "method scouting" protein purification strategies in aqueous two-phase systems: a study using model proteins.</a> Biotechnol Bioeng. 44, 626-635 (1994).</li><li>Arun, K. H., Kaul, C. L., Ramarao, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Green+fluorescent+proteins+in+receptor+research:+an+emerging+tool+for+drug+discovery.">Green fluorescent proteins in receptor research: an emerging tool for drug discovery.</a> J. Pharmacol. Toxicol. Methods. 51, 1-23 (2005).</li><li>Terrizzi, S. C., Banh, C., Brossay, . <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=L.A+Protocol+for+the+Production+of+KLRG1+Tetramer.">L.A Protocol for the Production of KLRG1 Tetramer.</a> J. Vis. Exp. (35), e1701-e1701 (2010).</li><li>Murphy, P. J. M., Morishima, Y., Kovacs, J. J., Yao, T. P., Pratt, W. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+the+dynamics+of+hsp90+action+on+the+glucocorticoid+receptor+by+acetylation/deacetylation+of+the+chaperone.">Regulation of the dynamics of hsp90 action on the glucocorticoid receptor by acetylation/deacetylation of the chaperone.</a> J. Biol. Chem. 280, 33792-33799 (2005).</li><li>Zeytuni, N., Zarivach, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+of+the+M.+magneticum+strain+AMB-1+Magnetosome+Associated+Protein+MamA&#916;41.">Purification of the M. magneticum strain AMB-1 Magnetosome Associated Protein MamA&#916;41.</a> J. Vis. Exp. (37), 10-3791 (2010).</li><li>Kong, Y., Li, X., Bai, G., Ma, G., Su, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+automatic+system+for+multidimensional+integrated+protein+chromatography.">An automatic system for multidimensional integrated protein chromatography.</a> J. Chromatogr. A. 1217, 6898-6904 (2010).</li><li>Camper, D. V., Viola, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fully+automated+protein+purification.">Fully automated protein purification.</a> Anal. Biochem. 393, 176-181 (2009).</li><li>Hammon, J., Palanivelu, D. V., Chen, J., Patel, C., Minor, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+green+fluorescent+protein+screen+for+identification+of+well-expressed+membrane+proteins+from+a+cohort+of+extremophilic+organisms.">A green fluorescent protein screen for identification of well-expressed membrane proteins from a cohort of extremophilic organisms.</a> Protein Sci. 18, 121-133 (2009).</li><li>Wu, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Using+green+and+red+fluorescent+proteins+to+teach+protein+expression,+purification,+and+crystallization.">Using green and red fluorescent proteins to teach protein expression, purification, and crystallization.</a> Biochem. Mol. Biol. Educ. 36, 43-54 (2008).</li><li>Queiroz, J. A., Tomaz, C. T., Cabral, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrophobic+interaction+chromatography+of+proteins.">Hydrophobic interaction chromatography of proteins.</a> J. Biotechnol. 87, 143-159 (2001).</li><li>McCue, J. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Theory+and+use+of+hydrophobic+interaction+chromatography+in+protein+purification+applications.">Theory and use of hydrophobic interaction chromatography in protein purification applications.</a> Methods Enzymol. 463, 405-414 (2009).</li></ol>

Seleccione reactivos de cromatografía y la instrumentación suplementario fueron proporcionados por Bio-Rad.

Técnicas de cromatografía líquida no han resultado útiles para la preparación de proteínas altamente purificadas necesarios para llevar a cabo inmunológico 6, 7 bioquímicos y estructurales de los estudios 8. Métodos de purificación de HIC más a menudo requieren determinación empírica de un medio preferido, y la estructura ligando, ligando densidad, y propiedades de la matriz de talón todo han demostrado su impacto en los resultados cromatográficos 2, 3. La columna de exploración automática es un enfoque eficaz para la selección de un medio de HIC para la optimización posterior y purificación de proteínas 4. El método de columna automatizado de exploración presentada puede ser fácilmente adaptado a diferentes estrategias de HIC de purificación de proteínas. Las alteraciones en la concentración de sal, la elección de la sal, el gradiente de sal, y el pH puede además mejorar las condiciones de purificación, y los efectos de variar estos parámetros esenciales se han examinado anteriormente 13,14. Eluato HIC que contiene un objetivo prote parcialmente purificadaen puede purificarse adicionalmente mediante una técnica cromatográfica complementarios, tales como cromatografía de intercambio iónico (IEX) o de filtración en gel / exclusión de tamaño cromatografía 9,10. Debido a su absorción de la luz única y características de emisión, el perfil de elución de las buenas prácticas agrarias que permiten detectar en línea y los enfoques de ejecución posterior. A tal fin, este protocolo adicional se puede adaptar para la purificación de fusión recombinantes GFP-proteínas, en el que una proteína diana no relacionado es &quot;etiquetado&quot; con GFP. GFP-etiquetados proteínas diana pueden ser detectados con luz UV 11 y se purificó utilizando diversos enfoques cromatográficos, incluyendo la estrategia de purificación de HIC se ha descrito anteriormente. Purificación de las buenas prácticas agrarias también se ha convertido en un elemento básico en los laboratorios de bioquímica pedagógica para la enseñanza de las técnicas modernas de la ciencia de proteínas 12. Mientras que la purificación de la proteína básica de HIC se puede realizar utilizando una cromatografía sustancialmente menos robusta Sytallo, la instrumentación que aquí se presenta tiene una serie de ventajas para ayudar en la obtención de resultados favorables. Notables beneficios de la utilización de un sistema altamente automatizado incluyen la mejora de run-to-run condición reproducibilidad, ahorro de tiempo, y la disminución de oportunidades para que el aire se introduzcan en el sistema 10. Sistema controlado mezcla tampón, que es facilitado por el sistema maximizador, permite una mayor coherencia en la preparación de tampón y reproducibilidad experimental. Dibujo de carga de muestra suficiente en el bucle de muestra dinámica para todos exploración se ejecuta además asegura la uniformidad de la muestra se añade a cada columna y permite la producción secuenciales sin interrupción o manual de recarga. Inyección de la muestra controlada desde el bucle muestra en la columna disminuye la variabilidad que se puede producir con la carga manual de las muestras. Un par de válvulas de selección de columna para permitir carreras muestras consecutivas, cada una utilizando una columna de HIC diferente, sin tener que replumb el sistema. Realización de Mul<html> TI-longitud de onda análisis es particularmente beneficioso cuando ensayando una proteína con un perfil espectrofotométrico único. Además de las buenas prácticas agrarias, citocromos, flavoproteínas y otras proteínas que contienen hemo-pueden beneficiarse de esta técnica. Dispositivos de control de conductividad y el pH de permitir la verificación en tiempo real de las condiciones experimentales. Fracción de la colección de Split eluido permite un manejo fracción de mejora y permite una fácil transferencia de métodos de análisis de ejecución después de que requieren un volumen de muestra mínimo (por ejemplo, ELISA, SDS-PAGE, Western Blot, y la electroforesis de microfluidos Experion). Mientras utiliza la línea fracción de segundo colector requiere de la sincronización manual, que permite la máxima flexibilidad en la selección de colector de fracciones. Los inconvenientes más importantes a utilizar como un sistema de cromatografía de columna de HIC robusta para exploración y purificación de proteínas incluyen el tiempo inicial y los gastos presupuestarios relacionados con la adquisición de instrumentos y la formación del operador. t &quot;&gt; El protocolo presentado aquí utiliza un Bio-Rad DuoFlow sistema de cromatografía;. sin embargo, la instrumentación igualmente robusto de otros fabricantes, tales como el Avant ÄKTA de GE Healthcare, también pueden utilizarse ser y son capaces de producir resultados equivalentes cromatografía Incluso comparables sistema tienen características únicas (por ejemplo, el método de programación, las limitaciones de nomenclatura de componentes, las preferencias del operador, y la escalabilidad) que deben ser considerados antes de iniciar un procedimiento de purificación o la adquisición de instrumentos.

<table border="1"><tbody><tr><td> Nombre del reactivo </td><td> Empresa </td><td> Número de catálogo </td><td> Comentarios (opcional) </td></tr><tr><td> <a href="http://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=BRCatgProductDetail&productID=223301" target="_blank">DuoFlow BioLogic Pathfinder 20 del Sistema</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> <a href="http://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=BRCatgProductDetail&productID=223301" target="_blank">7602257</a> </td><td> Incluye sistema maximizador, batidora, estación de trabajo F10, la válvula AVR7-3, UV QuadTec / Vis con detector de celda de flujo, colector de fracciones BIOFRAC, el software de productos biológicos y kit de inicio </td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&isFromSearch=true&productID=760-0408&vertical=LSR&parentCategoryGUID=22c495f1-36ff-44a3-9140-ee7e54d0b1ba" target="_blank">AVR9-8 flujo de la selección de la válvula</a><html></td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&isFromSearch=true&productID=760-0408&vertical=LSR&parentCategoryGUID=22c495f1-36ff-44a3-9140-ee7e54d0b1ba" target="_blank">7600408</a> </td><td> De alta presión de la válvula, 9-puerto, 8-posición, 3,500 psi (233 bar) de límite, para uso con el sistema BioLogic DuoFlow </td></tr><tr><td> La válvula de desvío SV3T-2 </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> 7600410 </td><td> La válvula de solenoide, 3-puerto, 2-posición, 30 psi (2 bar) límite, para uso con el sistema BioLogic DuoFlow </td></tr><tr><td> Corriente del divisor de la válvula </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td></td><td></td></tr><tr><td>tico = LSR y parentCategoryGUID = 22c495f1-36ff-44a3-9140-ee7e54d0b1ba &quot;target =&quot; _blank &quot;&gt; DynaLoop 25 Kit </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&isFromSearch=true&productID=750-0451&vertical=LSR&parentCategoryGUID=22c495f1-36ff-44a3-9140-ee7e54d0b1ba" target="_blank">7500451</a> </td><td> Deslizante del pistón kit de muestreo del lazo, incluye 25 ml DynaLoop deslizamiento del pistón de bucle, DynaLoop juego de piezas (# 750-0450) </td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/LSR/PDP/ec82e7b4-919e-428b-ac03-9adf1f50a48e/BioFractrade_Fraction_Collector" target="_blank">Colector de fracciones BIOFRAC</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> <a href="https://www.bio-rad.com/prd/en/US/LSR/PDP/ec82e7b4-919e-428b-ac03-9adf1f50a48e/BioFractrade_Fraction_Collector" target="_blank">7410002</a> </td><td> Dos fracción de col<html> lectores utilizan </td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&isFromSearch=true&productID=741-0088&vertical=LSR&parentCategoryGUID=ec82e7b4-919e-428b-ac03-9adf1f50a48e" target="_blank">BIOFRAC caída de la cabeza del adaptador de microplacas</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&isFromSearch=true&productID=741-0088&vertical=LSR&parentCategoryGUID=ec82e7b4-919e-428b-ac03-9adf1f50a48e" target="_blank">7410088</a> </td><td></td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&vertical=LSR&country=US&lang=en&productID=741-0017" target="_blank">BIOFRAC adaptador de la placa de microtitulación</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td>Y en el país = EE.UU. &amp; lang = es &amp; ProductID = 741-0017 &quot;target =&quot; _blank &quot;&gt; 7410017 </td><td></td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&isFromSearch=true&productID=750-0202&vertical=LSR&parentCategoryGUID=c140016b-1958-4a91-be4c-8645a4c8204f" target="_blank">UV Óptica Módulo</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&isFromSearch=true&productID=750-0202&vertical=LSR&parentCategoryGUID=c140016b-1958-4a91-be4c-8645a4c8204f" target="_blank">7500202</a> </td><td></td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=catProductDetail&isFromSearch=true&productID=760-1331&vertical=LSR&parentCategoryGUID=c4095dc1-9260-4431-b066-823b050048c8" target="_blank">Lámpara halógena</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> &lt;<html> un target = &quot;_blank&quot;&gt; 7601331 </td><td></td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=BRCatgProductDetail&productID=220901" target="_blank">Econo degradado de la bomba</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=BRCatgProductDetail&productID=220901" target="_blank">7319001</a> </td><td> bomba de gradiente para la purificación de proteínas de baja presión, incluye tubos y kit de accesorios </td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=BRCatgProductDetail&productID=224301" target="_blank">Experion Sistema</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td>bio-rad.com/prd/en/US/adirect/biorad? cmd = BRCatgProductDetail y ProductID = 224301 &quot;target =&quot; _blank &quot;&gt; 7007001 </td><td></td></tr><tr><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=BRCatgProductDetail&productID=224101" target="_blank">Experion Pro260 Kit de Análisis</a> </td><td> <a href="http://www.bio-rad.com/" target="_blank">Bio-Rad</a> </td><td> <a href="https://www.bio-rad.com/prd/en/US/adirect/biorad?cmd=BRCatgProductDetail&productID=224101" target="_blank">7007102</a> </td><td></td></tr><tr><td> HiTrap columna de HIC kit de selección </td><td> GE Healthcare </td><td> 28-4110-07 </td><td> Incluye 7 x 1 ml preenvasados ​​columnas de los medios de comunicación de HIC para el Movimiento Scout </td></tr><tr><td> GE Healthcare-a-Bio-Rad herrajes de las columnas </td><td> GE Healthcare </td><td> 18111251 y 18111257 </td><td></td></tr></tbody></table>

automated hydrophobic interaction chromatography column selection for use in protein purification

En contraste con otros métodos cromatográficos para las proteínas purificadores (por ejemplo, filtración en gel, afinidad y de intercambio iónico), cromatografía de interacción hidrofóbica (HIC) comúnmente requiere la determinación experimental (referido como cribado o &quot;exploración&quot;) con el fin de seleccionar el medio cromatográfico más adecuado para purificar una proteína dada 1. El método aquí presentado describe un enfoque automatizado a la exploración de un medio óptimo de HIC para ser utilizados en la purificación de proteínas. HIC separa las proteínas y otras biomoléculas de un lisado crudo basado en las diferencias de hidrofobicidad. Similar a la cromatografía de afinidad (AC) y cromatografía de intercambio iónico (IEX), HIC es capaz de concentrar la proteína de interés a medida que avanza a través del proceso cromatográfico. Las proteínas más adecuados para la purificación por HIC son aquellos con las regiones de la superficie hidrofóbica y capaces de soportar la exposición a la sal concentraciones superiores a 2 M municiónsulfato de Milenio ((NH 4) 2 SO 4). HIC se elige a menudo como un método de purificación de proteínas que carecen de una etiqueta de afinidad, y por lo tanto inadecuados para CA, y cuando IEX no proporciona purificación adecuada. Restos hidrófobos en la superficie de la proteína temporalmente unirse a un ligando no polar acoplado a una matriz inerte, inmóvil. La interacción entre la proteína y el ligando son altamente dependientes de la concentración de sal del tampón que fluye a través de la columna de cromatografía, con altas concentraciones iónicas fortalecimiento de la interacción proteína-ligando y haciendo que la proteína inmóvil (es decir, unido dentro de la columna) 2. Como sal disminución concentraciones, la interacción proteína-ligando se disipa, la proteína vuelve a ser móvil y se eluye de la columna. Varios medios de HIC están disponibles comercialmente en preenvasados ​​columnas, cada una contiene de varios ligandos hidrófobos (por ejemplo, S-butilo, butilo, octilo, y fenil) reticulado a diferentes densidades de perlas de agarosa de una especificaciónde diámetro IFIC 3. La columna de exploración automática permite un enfoque eficaz para la determinación de que los medios de HIC se debe emplear para futuros experimentos, optimización más exhaustivos y purificación de proteínas se ve un 4. La proteína específica que se purificó aquí es la proteína recombinante fluorescente verde (GFP), sin embargo, el enfoque puede ser adaptado para la purificación de otras proteínas con una o más regiones superficiales hidrofóbicas. GFP actúa como una proteína modelo de utilidad, debido a su estabilidad, máximo única absorción de luz de 397 nm, y la fluorescencia cuando se expone a la luz UV 5. Lisado bacteriano que contiene GFP tipo salvaje se preparó en un tampón de alto contenido en sal, se carga en un sistema de Bio-Rad medio DuoFlow cromatografía presión del líquido, y se adsorbe en columnas HiTrap HIC que contienen diferentes medios de HIC. La proteína se eluyó de las columnas y se analizó mediante en-línea y de ejecución posterior a métodos de detección. Mezcla de búfer, la inyección de dinamismo loop, col secuencialUMN selección, el análisis de múltiples longitudes de onda, y la recogida de división fracción eluato aumentado la funcionalidad del sistema y la reproducibilidad del método experimental.

Watch this Scientific Journal Video about Automated Hydrophobic Interaction Chromatography Column Selection for Use in Protein Purification at JoVE.com

Automated Hydrophobic Interaction Chromatography Column Selection for Use in Protein Purification

Un método automático para la identificación adecuados cromatografía de interacción hidrófoba (HIC) medios para ser utilizados en el proceso de purificación de proteínas se presenta. El método utiliza un sistema de líquido de presión media, incluyendo cromatografía de buffer blending automatizado, la inyección de la muestra dinámica de bucle, la selección secuencial de columna, el análisis de múltiples longitudes de onda, y la recolección dividida fracción del eluato.

La interacción hidrofóbica automatizada cromatografía en columna de selección para uso en la purificación de proteínas

In contrast to other chromatographic methods for purifying proteins (e.g. gel filtration, affinity, and ion exchange), hydrophobic interaction ...

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43.1K vistas.  Seattle University. Un método automático para la identificación adecuados cromatografía de interacción hidrófoba (HIC) medios para ser utilizados en el proceso de purificación de proteínas se presenta. El método utiliza un sistema de líquido de presión media, incluyendo cromatografía de buffer blending automatizado, la inyección de la muestra dinámica de bucle, la selección secuencial de columna, el análisis de múltiples longitudes de onda, y la recolección dividida fracci?...

Video: Automated Hydrophobic Interaction Chromatography Column Selection for Use in Protein Purification

Staining of Proteins in Gels with Coomassie G-250 without Organic Solvent and Acetic Acid

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents (Methanol, Ethanol or 2-Propanol) and acetic acid are used for fixation, staining and destaining of proteins in a gel after SDS-PAGE. To speed up the procedure, heating the staining solution in the microwave oven for a short time is frequently used. This usually results in evaporation of toxic or hazardous Methanol, Ethanol or 2-Propanol and a strong smell of acetic acid in the lab which should be avoided due to safety considerations. In a protocol originally published in two patent applications by E.M. Wondrak (US2001046709 (A1), US6319720 (B1)), an alternative composition of the staining solution is described in which no organic solvent or acid is used. The CBB is dissolved in bidistilled water (60-80mg of CBB G-250 per liter) and 35 mM HCl is added as the only other compound in the staining solution. The CBB staning of the gel is done after SDS-PAGE and thorough washing of the gel in bidistilled water. By heating the gel during the washing and staining steps, the process can be finished faster and no toxic or hazardous compunds are evaporating. The staining of proteins occurs already within 1 minute after heating the gel in staining solution and is fully developed after 15-30 min with a slightly blue background that is destained completely by prolonged washing of the stained gel in bidistilled water, without affecting the stained protein bands.

A short protocol for protein staining with Coomassie Brilliant Blue (CBB) G-250 in polyacrylamide gels is described without using organic solvents or acetic acid as in the classical staining procedures with CBB.

Tinción de las proteínas en geles con Coomassie G-250, sin ácido disolvente orgánico y el acético

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents ...

Investigación

Biología

Purification of the M. magneticum Strain AMB-1 Magnetosome Associated Protein MamA&Delta;41

Magnetotactic bacteria comprise a diverse group of aquatic microorganisms that are able to orientate themselves along geomagnetic fields. This behavior is believed to aid their search for suitable environments (1). This capability is conferred by the magnetosome, a subcellular organelle that consists of a linear-chain assembly of lipid vesicles each able to biomineralize and enclose a ~50-nm crystal of magnetite or greigite. A principle component of the magnetosome that was shown to be required for the formation of functional vesicles is MamA. MamA is a highly abundant magnetosome-associated protein which is one of the most characterized magnetosome-associated proteins in vivo (2-6). This article focuses on the purification of MamA, which despite being studied in vivo, no clear functional or structural details have been identified for it. Bioinformatics analysis suggested that MamA is a tetra-tricopeptide repeat (TPR) containing protein. TPR is a structural motif found as such or forming part of a bigger fold in a wide range of proteins, it serves as a template for protein-protein interactions and mediates multi-protein complexes (7). TPRs are involved in many crucial tasks in eukaryotic cell organelle processes and many bacterial pathways (8-14). In order to understand MamA, a unique TPR containing protein, highly purified protein is required as a first step. In this article, we present the purification protocol for a stable MamA deletion mutant (MamA&Delta;41) from M. magneticum AMB-1.

Purification of the &lt;em&gt;M. magneticum&lt;/em&gt; Strain AMB-1 Magnetosome Associated Protein MamA&amp;Delta;41

MamA is a unique Magnetosome associated protein which was shown to be involved in magnetosome activation. Here we present the purification protocol of MamA deletion mutant (MamA&Delta;41) from M. magneticum AMB-1.

La purificación de la M. magneticum Tensión AMB-1 magnetosomas proteína asociada MamAΔ41

Magnetotactic bacteria comprise a diverse group of aquatic microorganisms that are able to orientate themselves along geomagnetic fields. This behavior is ...

Bimolecular Fluorescence Complementation (BiFC) Assay for Protein-Protein Interaction in Onion Cells Using the Helios Gene Gun

Investigation of gene function in diverse organisms relies on knowledge of how the gene products interact with each other in their normal cellular environment. The Bimolecular Fluorescence Complementation (BiFC) Assay1 allows researchers to visualize protein-protein interactions in living cells and has become an essential research tool. This assay is based on the facilitated association of two fragments of a fluorescent protein (GFP) that are each fused to a potential interacting protein partner. The interaction of the two protein partners would facilitate the association of the N-terminal and C-terminal fragment of GFP, leading to fluorescence. For plant researchers, onion epidermal cells are an ideal experimental system for conducting the BiFC assay because of the ease in obtaining and preparing onion tissues and the direct visualization of fluorescence with minimal background fluorescence. The Helios Gene Gun (BioRad) is commonly used for bombarding plasmid DNA into onion cells. We demonstrate the use of Helios Gene Gun to introduce plasmid constructs for two interacting Arabidopsis thaliana transcription factors, SEUSS (SEU) and LEUNIG HOMOLOG (LUH)2 and the visualization of their interactions mediated by BiFC in onion epidermal cells.

Bimolecular Fluorescence Complementation BiFC Assay for Protein-Protein Interaction in Onion Cells Using the Helios Gene Gun

This article illustrates how to properly use the BioRad Helios Gene Gun to introduce plasmid DNA into onion epidermal cells and how to test for protein-protein interactions in onion cells based on the principle of Bimolecular Fluorescence Complementation (BiFC)

Bimolecular complementación de fluorescencia (BiFC) Ensayo de interacción proteína-proteína en las células de cebolla con la pistola de genes Helios

Investigation of gene function in diverse organisms relies on knowledge of how the gene products interact with each other in their normal cellular ...

Lipid Vesicle-mediated Affinity Chromatography using Magnetic Activated Cell Sorting (LIMACS): a Novel Method to Analyze Protein-lipid Interaction

The analysis of lipid protein interaction is difficult because lipids are embedded in cell membranes and therefore, inaccessible to most purification procedures. As an alternative, lipids can be coated on flat surfaces as used for lipid ELISA and Plasmon resonance spectroscopy. However, surface coating lipids do not form microdomain structures, which may be important for the lipid binding properties. Further, these methods do not allow for the purification of larger amounts of proteins binding to their target lipids.
 To overcome these limitations of testing lipid protein interaction and to purify lipid binding proteins we developed a novel method termed lipid vesicle-mediated affinity chromatography using magnetic-activated cell sorting (LIMACS). In this method, lipid vesicles are prepared with the target lipid and phosphatidylserine as the anchor lipid for Annexin V MACS. Phosphatidylserine is a ubiquitous cell membrane phospholipid that shows high affinity to the protein Annexin V. Using magnetic beads conjugated to Annexin V the phosphatidylserine-containing lipid vesicles will bind to the magnetic beads. When the lipid vesicles are incubated with a cell lysate the protein binding to the target lipid will also be bound to the beads and can be co-purified using MACS. This method can also be used to test if recombinant proteins reconstitute a protein complex binding to the target lipid. 
 We have used this method to show the interaction of atypical PKC (aPKC) with the sphingolipid ceramide and to co-purify prostate apoptosis response 4 (PAR-4), a protein binding to ceramide-associated aPKC. We have also used this method for the reconstitution of a ceramide-associated complex of recombinant aPKC with the cell polarity-related proteins Par6 and Cdc42. Since lipid vesicles can be prepared with a variety of sphingo- or phospholipids, LIMACS offers a versatile test for lipid-protein interaction in a lipid environment that resembles closely that of the cell membrane. Additional lipid protein complexes can be identified using proteomics analysis of lipid binding protein co-purified with the lipid vesicles.

Lipid Vesicle-mediated Affinity Chromatography using Magnetic Activated Cell Sorting LIMACS: a Novel Method to Analyze Protein-lipid Interaction

To test the interaction of a protein with its target lipid we used MACS and Annexin V-conjugated magnetic beads and lipid vesicles synthesized from the target lipid and Annexin V-binding phosphatidylserine. Proteins bound to the target lipid are co-purified and analyzed after elution from the beads.

Lípidos vesículas mediada por cromatografía de afinidad utilizando magnética clasificación de células activadas (LIMACS): un nuevo método para analizar la interacción de proteínas y lípidos

The analysis of lipid protein interaction is difficult because lipids are embedded in cell membranes and therefore, inaccessible to most purification ...

Purification of Hsp104, a Protein Disaggregase

Hsp104 is a hexameric AAA+ protein1 from yeast, which couples ATP hydrolysis to protein disaggregation2-10 (Fig. 1). This activity imparts two key selective advantages. First, renaturation of disordered aggregates by Hsp104 empowers yeast survival after various protein-misfolding stresses, including heat shock3,5,11,12. Second, remodeling of cross-beta amyloid fibrils by Hsp104 enables yeast to exploit myriad prions (infectious amyloids) as a reservoir of beneficial and heritable phenotypic variation13-22. Remarkably, Hsp104 directly remodels preamyloid oligomers and amyloid fibrils, including those comprised of the yeast prion proteins Sup35 and Ure223-30. This amyloid-remodeling functionality is a specialized facet of yeast Hsp104. The E. coli orthologue, ClpB, fails to remodel preamyloid oligomers or amyloid fibrils26,31,32.
Hsp104 orthologues are found in all kingdoms of life except, perplexingly, animals. Indeed, whether animal cells possess any enzymatic system that couples protein disaggregation to renaturation (rather than degradation) remains unknown33-35. Thus, we and others have proposed that Hsp104 might be developed as a therapeutic agent for various neurodegenerative diseases connected with the misfolding of specific proteins into toxic preamyloid oligomers and amyloid fibrils4,7,23,36-38. There are no treatments that directly target the aggregated species associated with these diseases. Yet, Hsp104 dissolves toxic oligomers and amyloid fibrils composed of alpha-synuclein, which are connected with Parkinson's Disease23 as well as amyloid forms of PrP39. Importantly, Hsp104 reduces protein aggregation and ameliorates neurodegeneration in rodent models of Parkinson's Disease23 and Huntington's disease38. Ideally, to optimize therapy and minimize side effects, Hsp104 would be engineered and potentiated to selectively remodel specific aggregates central to the disease in question4,7. However, the limited structural and mechanistic understanding of how Hsp104 disaggregates such a diverse repertoire of aggregated structures and unrelated proteins frustrates these endeavors30,40-42.
To understand the structure and mechanism of Hsp104, it is essential to study the pure protein and reconstitute its disaggregase activity with minimal components. Hsp104 is a 102kDa protein with a pI of ~5.3, which hexamerizes in the presence of ADP or ATP, or at high protein concentrations in the absence of nucleotide43-46. Here, we describe an optimized protocol for the purification of highly active, stable Hsp104 from E. coli. The use of E. coli allows simplified large-scale production and our method can be performed quickly and reliably for numerous Hsp104 variants. Our protocol increases Hsp104 purity and simplifies His6-tag removal compared to a previous purification method from E. coli47. Moreover, our protocol is more facile and convenient than two more recent protocols26,48.

Here, we describe a protocol for the purification of highly active Hsp104, a hexameric AAA+ protein from yeast, which couples ATP hydrolysis to protein disaggregation. This scheme exploits a His6-tagged construct for affinity purification from E. coli followed by anion-exchange chromatography, His6-tag removal with TEV protease, and size-exclusion chromatography.

La purificación de Hsp104, una proteína Disaggregase

Hsp104 is a hexameric AAA+ protein1 from yeast, which couples ATP hydrolysis to protein disaggregation2-10 (Fig. 1). This activity imparts two key ...

A Protocol for Phage Display and Affinity Selection Using Recombinant Protein Baits

Using recombinant phage as a scaffold to present various protein portions encoded by a directionally cloned cDNA library to immobilized bait molecules is an efficient means to discover interactions. The technique has largely been used to discover protein-protein interactions but the bait molecule to be challenged need not be restricted to proteins. The protocol presented here has been optimized to allow a modest number of baits to be screened in replicates to maximize the identification of independent clones presenting the same protein. This permits greater confidence that interacting proteins identified are legitimate interactors of the bait molecule. Monitoring the phage titer after each affinity selection round provides information on how the affinity selection is progressing as well as on the efficacy of negative controls. One means of titering the phage, and how and what to prepare in advance to allow this process to progress as efficiently as possible, is presented. Attributes of amplicons retrieved following isolation of independent plaque are highlighted that can be used to ascertain how well the affinity selection has progressed. Trouble shooting techniques to minimize false positives or to bypass persistently recovered phage are explained. Means of reducing viral contamination flare up are discussed.

Phage display is a powerful technique to capture proteins or protein moieties that interact with an immobilized molecule of interest. Once a decision of the type of phage cDNA library to create and screen has been made, the protocol described here permits efficient affinity selection leading to identification of interactors.

Un Protocolo de fagos y de selección de afinidad utilizando cebos proteína recombinante

Using  recombinant phage as a scaffold to present various protein portions encoded by  a directionally cloned cDNA library to immobilized bait molecules ...

Identifying Protein-protein Interaction in Drosophila Adult Heads by Tandem Affinity Purification (TAP)

Genetic screens conducted using Drosophila melanogaster (fruit fly) have made numerous milestone discoveries in the advance of biological sciences. However, the use of biochemical screens aimed at extending the knowledge gained from genetic analysis was explored only recently. Here we describe a method to purify the protein complex that associates with any protein of interest from adult fly heads. This method takes advantage of the Drosophila GAL4/UAS system to express a bait protein fused with a Tandem Affinity Purification (TAP) tag in fly neurons in vivo, and then implements two rounds of purification using a TAP procedure similar to the one originally established in yeast1 to purify the interacting protein complex. At the end of this procedure, a mixture of multiple protein complexes is obtained whose molecular identities can be determined by mass spectrometry. Validation of the candidate proteins will benefit from the resource and ease of performing loss-of-function studies in flies. Similar approaches can be applied to other fly tissues. We believe that the combination of genetic manipulations and this proteomic approach in the fly model system holds tremendous potential for tackling fundamental problems in the field of neurobiology and beyond.

Identifying Protein-protein Interaction in Drosophila Adult Heads by Tandem Affinity Purification TAP

Drosophila is famous for its powerful genetic manipulation, but not for its suitability of in-depth biochemical analysis. Here we present a TAP-based procedure to identify interacting partners of any protein of interest from the fly brain. This procedure can potentially lead to new avenues of research.

La identificación de la interacción proteína-proteína en<em&gt; Drosophila</em&gt; Jefes adultas por Tandem Affinity purificación (TAP)

Genetic screens conducted using Drosophila melanogaster (fruit fly) have made numerous milestone discoveries in the advance of biological sciences. ...

Identifying Protein-protein Interaction Sites Using Peptide Arrays

Protein-protein interactions mediate most of the processes in the living cell and control homeostasis of the organism. Impaired protein interactions may result in disease, making protein interactions important drug targets. It is thus highly important to understand these interactions at the molecular level. Protein interactions are studied using a variety of techniques ranging from cellular and biochemical assays to quantitative biophysical assays, and these may be performed either with full-length proteins, with protein domains or with peptides. Peptides serve as excellent tools to study protein interactions since peptides can be easily synthesized and allow the focusing on specific interaction sites. Peptide arrays enable the identification of the interaction sites between two proteins as well as screening for peptides that bind the target protein for therapeutic purposes. They also allow high throughput SAR studies. For identification of binding sites, a typical peptide array usually contains partly overlapping 10-20 residues peptides derived from the full sequences of one or more partner proteins of the desired target protein. Screening the array for binding the target protein reveals the binding peptides, corresponding to the binding sites in the partner proteins, in an easy and fast method using only small amount of protein.
In this article we describe a protocol for screening peptide arrays for mapping the interaction sites between a target protein and its partners. The peptide array is designed based on the sequences of the partner proteins taking into account their secondary structures. The arrays used in this protocol were Celluspots arrays prepared by INTAVIS Bioanalytical Instruments. The array is blocked to prevent unspecific binding and then incubated with the studied protein. Detection using an antibody reveals the binding peptides corresponding to the specific interaction sites between the proteins.

Peptide array screening is a high throughput assay for identifying protein-protein interaction sites. This allows mapping multiple interactions of a target protein and can serve as a method for identifying sites for inhibitors that target a protein. Here we describe a protocol for screening and analyzing peptide arrays.

La identificación de sitios de interacción proteína-proteína utilizando péptido arrays

Protein-protein interactions mediate most of the processes in the living cell and control homeostasis of the organism. Impaired protein interactions may ...

Genome-wide Protein-protein Interaction Screening by Protein-fragment Complementation Assay (PCA) in Living Cells

Proteins are the building blocks, effectors and signal mediators of cellular processes. A protein&#8217;s function, regulation and localization often depend on its interactions with other proteins. Here, we describe a protocol for the yeast protein-fragment complementation assay (PCA), a powerful method to detect direct and proximal associations between proteins in living cells. The interaction between two proteins, each fused to a dihydrofolate reductase (DHFR) protein fragment, translates into growth of yeast strains in presence of the drug methotrexate (MTX). Differential fitness, resulting from different amounts of reconstituted DHFR enzyme, can be quantified on high-density colony arrays, allowing to differentiate interacting from non-interacting bait-prey pairs. The high-throughput protocol presented here is performed using a robotic platform that parallelizes mating of bait and prey strains carrying complementary DHFR-fragment fusion proteins and the survival assay on MTX. This protocol allows to systematically test for thousands of protein-protein interactions (PPIs) involving bait proteins of interest and offers several advantages over other PPI detection assays, including the study of proteins expressed from their endogenous promoters without the need for modifying protein localization and for the assembly of complex reporter constructs.

Genome-wide Protein-protein Interaction Screening by Protein-fragment Complementation Assay PCA in Living Cells

Proteins interact with each other and these interactions determine in a large part their functions. Protein interaction partners can be identified at high-throughput in vivo using a yeast fitness assay based on the dihydrofolate reductase protein-fragment complementation assay (DHFR-PCA).

Genoma toda la Proteína-proteína interacción Screening por Complementación de ensayo de proteínas-fragmento (PCA) en las células vivas

Proteins are the building blocks, effectors and signal mediators of cellular processes. A protein&#8217;s function, regulation and localization often ...

Luciferase Complementation Imaging Assay in Nicotiana benthamiana Leaves for Transiently Determining Protein-protein Interaction Dynamics

Protein-protein interactions are fundamental mechanisms for relaying signal transduction in most cellular processes; therefore, identification of novel protein-protein interaction pairs and monitoring protein interaction dynamics are of particular interest for revealing how plants respond to environmental factors and/or developmental signals. A plethora of approaches have been developed to examine protein-protein interactions, either in vitro or in vivo. Among them, the recently established luciferase complementation imaging (LCI) assay is the simplest and fastest method for demonstrating in vivo protein-protein interactions. In this assay, protein A or protein B is fused with the amino-terminal or carboxyl-terminal half of luciferase, respectively. When protein A interacts with protein B, the two halves of luciferase will be reconstituted to form a functional and active luciferase enzyme. Luciferase activity can be recorded with a luminometer or CCD-camera. Compared with other approaches, the LCI assay shows protein-protein interactions both qualitatively and quantitatively. Agrobacterium infiltration in Nicotiana benthamiana leaves is a widely used system for transient protein expression. With the combination of LCI and transient expression, these approaches show that the physical interaction between COP1 and SPA1 was gradually reduced after jasmonate treatment.

Luciferase Complementation Imaging Assay in Nicotiana benthamiana Leaves for Transiently Determining Protein-protein Interaction Dynamics

This manuscript describes an easy and rapid experimental procedure for determining protein-protein interactions based on the measurement of luciferase activity.

Complementación de luciferase imagen ensayo en hojas de Nicotiana benthamiana para determinar transitoriamente proteínas interacción dinámica

Protein-protein interactions are fundamental mechanisms for relaying signal transduction in most cellular processes; therefore, identification of novel ...