title: Colicin S8 export: extracellular and cytoplasmic colicin are different.
abstract: The properties of colicin S8 are different for the cytoplasmic, periplasmic and extracellular protein. Interactions with its specific receptors reflect this. Active cell extracts separate into a non-anionic along with an anionic fraction by DEAE-Sephacell chromatography. Previously, we have purified cell-associated colicin S8 as an aggregation of highly related polypeptides; cytoplasmic colicin S8 seems to be post-translationally processed into an aggregation of polypeptides of molecular mass ranging from 45,000 Da to 60,000 Da. We suggest that a conformational change to colicin S8 may occur related to the export process.
authors.affiliation: Centro de Ingenieria Genética, Facultad de Ciencias, Universidad de los Andes, Ruta 5853, La Hechicera 510, ZP.9995-P, Mérida, Venezuela. malena03@cantv.net
authors.forename: Maria-Elena
authors.initials: ME
authors.lastname: Garcia Diaz
authors.forename: Juan Luis
authors.initials: JL
authors.lastname: Concepción Curbelo
mesh_terms: D002852:Chromatography, Ion Exchange; D003087:Colicins / Q000302:isolation & purification / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D005110:Extracellular Space / Q000378:metabolism; D021381:Protein Transport
chemical_list: D003087:Colicins; D029968:Escherichia coli Proteins; C483612:colicin S8, E coli