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Interaction of the Bacillus subtilis phage Φ105 repressor DNA: a genetic analysis

(1988) EMBO JOURNAL. 7(3). p.859-866
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Abstract
The Bacillus subtilis phage phi 105 repressor specifically recognizes a 14-bp operator sequence which does not exhibit 2-fold rotational symmetry. To facilitate a genetic analysis of this sequence-dependent DNA binding a B. subtilis strain was constructed in which mutations affecting the phi 105 repressor-operator interaction cause a selectable phenotype, chloramphenicol resistance. After in vivo mutagenesis, we isolated and mapped 22 different mutations in the repressor coding sequence, 15 of which are missense substitutions. These are exclusively located in the N-terminal part (positions 1-43) of the 144 residue long polypeptide. Two nonsense mutants, at positions 70 and 89, respectively, still show partial repressor activity. These data suggest that the phi 105 repressor consists of at least two independently folding structural domains, of which the N-terminal is involved in operator binding. Twelve missense mutations are clustered in a region extending from Gln-18 to Arg-37, which we propose to be the DNA-binding alpha-helix--beta-turn--alpha-helix motif, common to all lambda Cro-like repressors. The second ('recognition') helix shows significant homology with the corresponding sequence in Tn3 resolvase, and there is also a striking similarity between the phi 105 operator and the consensus sequence for a Tn3 res half-site. Based on these observations, and on the previously isolated phi 105 0c mutants, we tentatively assign some specific contacts between base pairs from the first half of a phi 105 operator site and amino acids from the repressor's 'recognition helix'.

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Chicago
Van Kaer, Luc, Yannick Gansemans, Marc Van Montagu, and Patrick Dhaese. 1988. “Interaction of the Bacillus Subtilis Phage Φ105 Repressor DNA: a Genetic Analysis.” Embo Journal 7 (3): 859–866.
APA
Van Kaer, Luc, Gansemans, Y., Van Montagu, M., & Dhaese, P. (1988). Interaction of the Bacillus subtilis phage Φ105 repressor DNA: a genetic analysis. EMBO JOURNAL, 7(3), 859–866.
Vancouver
1.
Van Kaer L, Gansemans Y, Van Montagu M, Dhaese P. Interaction of the Bacillus subtilis phage Φ105 repressor DNA: a genetic analysis. EMBO JOURNAL. 1988;7(3):859–66.
MLA
Van Kaer, Luc, Yannick Gansemans, Marc Van Montagu, et al. “Interaction of the Bacillus Subtilis Phage Φ105 Repressor DNA: a Genetic Analysis.” EMBO JOURNAL 7.3 (1988): 859–866. Print.
@article{1919017,
  abstract     = {The Bacillus subtilis phage phi 105 repressor specifically recognizes a 14-bp operator sequence which does not exhibit 2-fold rotational symmetry. To facilitate a genetic analysis of this sequence-dependent DNA binding a B. subtilis strain was constructed in which mutations affecting the phi 105 repressor-operator interaction cause a selectable phenotype, chloramphenicol resistance. After in vivo mutagenesis, we isolated and mapped 22 different mutations in the repressor coding sequence, 15 of which are missense substitutions. These are exclusively located in the N-terminal part (positions 1-43) of the 144 residue long polypeptide. Two nonsense mutants, at positions 70 and 89, respectively, still show partial repressor activity. These data suggest that the phi 105 repressor consists of at least two independently folding structural domains, of which the N-terminal is involved in operator binding. Twelve missense mutations are clustered in a region extending from Gln-18 to Arg-37, which we propose to be the DNA-binding alpha-helix--beta-turn--alpha-helix motif, common to all lambda Cro-like repressors. The second ('recognition') helix shows significant homology with the corresponding sequence in Tn3 resolvase, and there is also a striking similarity between the phi 105 operator and the consensus sequence for a Tn3 res half-site. Based on these observations, and on the previously isolated phi 105 0c mutants, we tentatively assign some specific contacts between base pairs from the first half of a phi 105 operator site and amino acids from the repressor's 'recognition helix'.},
  author       = {Van Kaer, Luc and Gansemans, Yannick and Van Montagu, Marc and Dhaese, Patrick},
  issn         = {0261-4189},
  journal      = {EMBO JOURNAL},
  language     = {eng},
  number       = {3},
  pages        = {859--866},
  title        = {Interaction of the Bacillus subtilis phage \ensuremath{\Phi}105 repressor DNA: a genetic analysis},
  url          = {http://www.ncbi.nlm.nih.gov/pmc/articles/PMC454403/?tool=pubmed},
  volume       = {7},
  year         = {1988},
}