RESUMEN
The major envelope protein, GP5, in porcine reproductive and respiratory syndrome virus (PRRSV) plays critical roles in the assembly, invasion and immune response of PRRSV particle, and is one of the mostly studied candidates in the development of recombinant vaccines. In this research, a purification process including immobilized metal affinity chromatography (IMAC) and hydrophobic interaction chromatography (HIC) was developed to prepare recombinant envelope protein GP5 with His-tag from an E. coli strain transformed with pGEM-ORF5. The result of cell culture indicated that His-tagged GP5 protein was expressed mainly in soluble form. After cell disruption, His-tagged GP5 protein was successfully purified by Ni(2+)-chelating Sepharose Fast Flow with a yield and purity of 80.5% and 48%, respectively. Recombinant GP5 protein was further purified by HIC to achieve a purity of 95%. Moreover, the purified rGP5 is shown in monomeric form contrasting the dimeric or tetrameric form when purified by a CEX-HIC process directly from PRRSV virions as reported in a previous study.
Asunto(s)
Cromatografía de Afinidad/métodos , Síndrome Respiratorio y de la Reproducción Porcina/virología , Virus del Síndrome Respiratorio y Reproductivo Porcino/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas del Envoltorio Viral/aislamiento & purificación , Animales , Clonación Molecular , Escherichia coli/genética , Interacciones Hidrofóbicas e Hidrofílicas , Metales/química , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Porcinos , Vacunas Sintéticas/química , Vacunas Sintéticas/genética , Vacunas Sintéticas/aislamiento & purificación , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/genéticaRESUMEN
The quantity of greenhouse gas emissions (net carbon emissions) of corn-based fuel ethanol, which is known as an alternative for fossil fuel is an important criteria for evaluating its sustainability. The methodology of carbon balance analysis for fuel ethanol from corn was developed based on principles of life cycle analysis. For the production state of fuel ethanol from summer corn in China, carbon budgets in overall life cycle of the ethanol were evaluated and its main influence factors were identified. It presents that corn-based fuel ethanol has no obvious reduction of carbon emissions than gasoline, and potential improvement in carbon emission of the life cycle of corn ethanol could be achieved by reducing the nitrogen fertilizer and irrigation electricity used in the corn farming and energy consumption in the ethanol conversion process.
