title: A FhuA mutant of Escherichia coli is infected by phage T1-independent of TonB.
abstract: Infection of Escherichia coli K-12 by phages T1 and phi 80 requires the FhuA outer membrane protein and the TonB protein. Mutations in the N-terminal globular domain close to the predicted channel in the beta-barrel of FhuA were created. The FhuA Delta 107-111 N104K K110D L111P mutant and the FhuA(L(109)DPNGLK(110)) insertion mutant were sensitive to phage T1, but nearly resistant to phage phi 80. FhuA Delta 107-111 N104K K110D L111P mediated phage T1 infection in a tonB mutant without formation of TonB-independent phage T1 host-range mutants. The FhuA mutants showed no altered sensitivity to phage T5. Although the phages share overlapping binding sites in FhuA, the structural alterations elicited by the mutations resulted in very different phage sensitivities. In the FhuA deletion mutant, the TonB requirement for phage T1 infection was partially bypassed.
authors.affiliation: Mikrobiologie/Membranphysiologie, Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tuebingen, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Langenscheid
authors.forename: Helmut
authors.initials: H
authors.lastname: Killmann
authors.forename: Volkmar
authors.initials: V
authors.lastname: Braun
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D001426:Bacterial Proteins / Q000502:physiology*; D003090:Coliphages / Q000254:growth & development*; D004926:Escherichia coli / Q000235:genetics* / Q000821:virology*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D005798:Genes, Bacterial; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D020125:Mutation, Missense; D011487:Protein Conformation; D011991:Receptors, Virus / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D017384:Sequence Deletion; D013604:T-Phages / Q000254:growth & development*; D010948:Viral Plaque Assay
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C050900:FhuA protein, E coli; D008565:Membrane Proteins; D011991:Receptors, Virus; C057616:tonB protein, Bacteria; C489181:tonB protein, E coli