An Escherichia coli DNA topoisomerase I mutant has a compensatory mutation that alters two residues between functional domains of the DNA gyrase A protein.
AUTOR(ES)
Oram, M
RESUMO
Nucleotide sequence analysis revealed that the compensatory gyrA mutation in Escherichia coli DM750 affects DNA supercoiling by interchanging the identities of Ala-569 and Thr-586 in the DNA gyrase A subunit. These residues flank Arg-571, a site for trypsin cleavage that splits gyrase A protein between DNA breakage-reunion and DNA-binding domains. The putative interdomain locations of the DM750 mutation and that of E. coli DM800 (in gyrase B protein) suggests that these compensatory mutations may reduce DNA supercoiling activity by altering allosteric interactions in the gyrase complex.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=206131Documentos Relacionados
- Effects of DNA gyrase inhibitors in Escherichia coli topoisomerase I mutants.
- Expression of yeast DNA topoisomerase I can complement a conditional-lethal DNA topoisomerase I mutation in Escherichia coli.
- A two-subunit type I DNA topoisomerase (reverse gyrase) from an extreme hyperthermophile.
- A topoisomerase from Escherichia coli related to DNA gyrase.
- The C-terminal domain of the Escherichia coli DNA gyrase A subunit is a DNA-binding protein.