1QPM

NMR STRUCTURE OF THE MU BACTERIOPHAGE REPRESSOR DNA-BINDING DOMAIN

1QPM の概要

• エントリーDOI: 10.2210/pdb1qpm/pdb
• 分子名称: PROTEIN (MU BACTERIOPHAGE C REPRESSOR PROTEIN) (1 entity in total)
• 機能のキーワード: helix-turn-helix, mu bacteriophage, repressor, viral protein
• 由来する生物種: Enterobacteria phage Mu
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 7543.70

構造登録者

Ilangovan, U.,Wojciak, J.M.,Connolly, K.M.,Clubb, R.T. (登録日: 1999-05-26, 公開日: 1999-06-04, 最終更新日: 2024-05-22)

主引用文献

Ilangovan, U.,Wojciak, J.M.,Connolly, K.M.,Clubb, R.T.
NMR structure and functional studies of the Mu repressor DNA-binding domain.
Biochemistry, 38:8367-8376, 1999

PubMed Abstract: The repressor protein of bacteriophage Mu establishes and maintains lysogeny by shutting down transposition functions needed for phage DNA replication. It interacts with several repeated DNA sequences within the early operator, preventing transcription from two divergent promoters. It also directly represses transposition by competing with the MuA transposase for an internal activation sequence (IAS) that is coincident with the operator and required for efficient transposition. The transposase and repressor proteins compete for the operator/IAS region using homologous DNA-binding domains located at their amino termini. Here we present the solution structure of the amino-terminal DNA-binding domain from the repressor protein determined by heteronuclear multidimensional nuclear magnetic resonance spectroscopy. The structure of the repressor DNA-binding domain provides insights into the molecular basis of several temperature sensitive mutations and, in combination with complementary experiments using flourescence anisotropy, surface plasmon resonance, and circular dichroism, defines the structural and biochemical differences between the transposase and repressor DNA-binding modules. We find that the repressor and enhancer domains possess similar three-dimensional structures, thermostabilities, and intrinsic affinities for DNA. This latter result suggests that the higher affinity of the full-length repressor relative to that of the MuA transposase protein originates from cooperative interactions between repressor protomers and not from intrinsic differences in their DNA-binding domains. In addition, we present the results of nucleotide and amino acid mutagenesis which delimits the minimal repressor DNA-binding module and coarsely defines the nucleotide dependence of repressor binding.

PubMed: 10387082
DOI: 10.1021/bi990530b

実験手法

SOLUTION NMR