RRC ID 30136
Author Yoshida K, Fujita Y, Sarai A.
Title Missense mutations in the Bacillus subtilis gnt repressor that diminish operator binding ability.
Journal J. Mol. Biol.
Abstract The Bacillus subtilis gnt operon is negatively regulated by the gnt repressor (GntR, 243 amino acids), which is antagonized by gluconate. The GntR protein belongs to a new family of bacterial regulatory proteins (GntR family). To locate the DNA-binding domain of the GntR protein, we obtained mutations of this protein, by hydroxylamine mutagenesis, which diminish its operator binding ability. Sequence analysis of these mutations indicated that the mutant GntR proteins (GntR43L, GntR66T, GntR74K and GntR75Q) had amino acid substitutions (Ser43 to Leu, Ala66 to Thr, Glu74 to Lys and Arg75 to Gln), respectively. They were all located within the N-terminal conserved region of the GntR family. In vivo and in vitro analysis of these GntR proteins indicated that their relative operator binding abilities became weaker in the order of GntR (wild type), GntR66T, GntR75Q, GntR74K and GntR43L. The equilibrium dissociation constants of GntR (wild type), GntR66T, GntR75Q and GntR74K as to operator binding were determined by gel retardation assays to be 0.43, 2.6, 4.2 and 8.8 M x 10(-10), respectively.
Volume 231(2)
Pages 167-74
Published 1993-5-20
PII S0022283683712702
PMID 8510140
MeSH Amino Acid Sequence Bacillus subtilis / genetics* DNA-Binding Proteins / genetics* Escherichia coli Proteins* Gene Expression Regulation, Bacterial* Genes, Bacterial Molecular Sequence Data Multigene Family Mutation Operator Regions, Genetic / genetics* Repressor Proteins / genetics* Sequence Analysis, DNA Sequence Homology, Amino Acid Transcription Factors*
IF 4.894
Times Cited 26
Prokaryotes E. coli ME9648 ME9649 ME9650 ME9651 ME9652 ME9654