title: Periplasmic expression and recovery of human interferon gamma in Escherichia coli.
abstract: A synthetic human interferon gamma (hIFN-gamma) gene was fused to SP1 and SP3, two Sec-dependent artificial signal peptides to transport the hIFN-gamma to the periplasm of Escherichia coli BL21-SI. The processing efficiency of both SP1-hIFN-gamma and SP3-hIFN-gamma was dependent on the culture medium as well as the post-induction temperature. Both precursors were processed completely when cells were cultured using minimal medium and a post-induction temperature of 32.5 degrees C, and only the processed hIFN-gamma was detected. The SP3 signal peptide was more efficient than SP1 for the secretion of hIFN-gamma. Sixty percent of the total hIFN-gamma was secreted to the periplasm using the SP3 signal peptide and a post-induction temperature of 20 degrees C. Using Tris-sucrose-dithiothreitol (TSD) hypertonic buffer, the periplasmic soluble hINF-gamma was recovered with a purity of 85%.
authors.affiliation: División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, Col. Lomas 4a. Sección, C.P. 78216 San Luis Potosí, SLP, Mexico.
authors.forename: Victor E
authors.initials: VE
authors.lastname: Balderas Hernández
authors.forename: Luz M T
authors.initials: LM
authors.lastname: Paz Maldonado
authors.forename: Emilio
authors.initials: E
authors.lastname: Medina Rivero
authors.forename: Ana P
authors.initials: AP
authors.lastname: Barba de la Rosa
authors.forename: Juan F
authors.initials: JF
authors.lastname: Jiménez-Bremont
authors.forename: Leandro G
authors.initials: LG
authors.lastname: Ordoñez Acevedo
authors.forename: Antonio
authors.initials: A
authors.lastname: De León Rodríguez
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004926:Escherichia coli / Q000378:metabolism* / Q000648:ultrastructure; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D019897:Periplasm / Q000378:metabolism*; D021382:Protein Sorting Signals / Q000235:genetics; D013696:Temperature
chemical_list: D021382:Protein Sorting Signals; D007371:Interferon-gamma