Inactivation of colicin Y by intramembrane helix-helix interaction with its immunity protein
Language English Country England, Great Britain Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
18803667
DOI
10.1111/j.1742-4658.2008.06662.x
PII: EJB6662
Knihovny.cz E-resources
- MeSH
- Escherichia coli K12 chemistry immunology MeSH
- Immunity MeSH
- Colicins chemistry metabolism MeSH
- Escherichia coli Proteins chemistry metabolism MeSH
- Protein Structure, Secondary MeSH
- Protein Binding MeSH
- Binding Sites MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- colicin Y protein, E coli MeSH Browser
- Cyi protein, E coli MeSH Browser
- Colicins MeSH
- Escherichia coli Proteins MeSH
The construction of hybrids between colicins U and Y and the mutagenesis of the colicin Y gene (cya) have revealed amino acid residues important for interactions between colicin Y and its cognate immunity protein (Cyi). Four such residues (I578, T582, Y586 and V590) were found in helices 8 and 9 of the colicin Y pore-forming domain. To verify the importance of these residues, the corresponding amino acids in the colicin B protein were mutated to the residues present in colicin Y. An Escherichia coli strain with cloned colicin Y immunity gene (cyi) inactivated this mutant, but not the wild-type colicin B. In addition, interacting amino acid pairs in Cya and Cyi were identified using a set of Cyi point mutant strains. These data are consistent with antiparallel helix-helix interactions between Cyi helix T3 and Cya helix 8 of the pore-forming domain as a molecular mechanism of colicin Y inactivation by its immunity protein.
References provided by Crossref.org
Colicin U from Shigella boydii Forms Voltage-Dependent Pores
