title: Comparison of the uptake systems for the entry of various BtuB group colicins into Escherichia coli.
abstract: Colicins A, E1, E2 and E3 belong to the BtuB group of colicins. The NH2-terminal region of colicin A is required for translocation, and defects in this region cannot be overcome by osmotic shock of sensitive cells. In addition to BtuB, colicin A requires OmpF for efficient uptake by sensitive cells. The roles of BtuB and OmpF in translocation and binding to the receptor of the colicins A, E1, E2 and E3 were compared. The results suggest that for colicin A OmpF is used both as a receptor and for translocation across the outer membrane. In contrast, for colicin E1, OmpF is used neither as a receptor nor for translocation. For colicins E2 and E3, the situation is intermediate: only BtuB is used as a receptor but both BtuB and OmpF are involved in the translocation step.
authors.affiliation: Centre de Biochimie et de Biologie Moléculaire du Centre National de la Recherche Scientifique, Marseille, France.
authors.forename: H
authors.initials: H
authors.lastname: Benedetti
authors.forename: M
authors.initials: M
authors.lastname: Frenette
authors.forename: D
authors.initials: D
authors.lastname: Baty
authors.forename: R
authors.initials: R
authors.lastname: Lloubès
authors.forename: V
authors.initials: V
authors.lastname: Geli
authors.forename: C
authors.initials: C
authors.lastname: Lazdunski
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001693:Biological Transport, Active; D003087:Colicins / Q000493:pharmacokinetics*; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins; D009154:Mutation; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D001425:Bacterial Outer Membrane Proteins; D003087:Colicins; D029968:Escherichia coli Proteins; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; C028593:colicin receptor, E coli