title: Chemical trapping of the dynamic MutS-MutL complex formed in DNA mismatch repair in Escherichia coli.
abstract: The ternary complex comprising MutS, MutL, and DNA is a key intermediate in DNA mismatch repair. We used chemical cross-linking and fluorescence resonance energy transfer (FRET) to study the interaction between MutS and MutL and to shed light onto the structure of this complex. Via chemical cross-linking, we could stabilize this dynamic complex and identify the structural features of key events in DNA mismatch repair. We could show that in the complex between MutS and MutL the mismatch-binding and connector domains of MutS are in proximity to the N-terminal ATPase domain of MutL. The DNA- and nucleotide-dependent complex formation could be monitored by FRET using single cysteine variants labeled in the connector domain of MutS and the transducer domain of MutL, respectively. In addition, we could trap MutS after an ATP-induced conformational change by an intramolecular cross-link between Cys-93 of the mismatch-binding domain and Cys-239 of the connector domain.
authors: Institute for Biochemistry, FB 08, Justus Liebig University, D-35392 Giessen, Germany.
authors: Ines
authors: I
authors: Winkler
authors: Andreas D
authors: AD
authors: Marx
authors: Damien
authors: D
authors: Lariviere
authors: Roger J
authors: RJ
authors: Heinze
authors: Michele
authors: M
authors: Cristovao
authors: Annet
authors: A
authors: Reumer
authors: Ute
authors: U
authors: Curth
authors: Titia K
authors: TK
authors: Sixma
authors: Peter
authors: P
authors: Friedhoff
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry*; D000255:Adenosine Triphosphate / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000737:chemistry / Q000494:pharmacology; D003545:Cysteine / Q000737:chemistry; D053843:DNA Mismatch Repair; D004260:DNA Repair; D045643:DNA Repair Enzymes / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D004706:Endodeoxyribonucleases / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods; D015964:Gene Expression Regulation, Bacterial; D000070956:MutL Proteins; D051719:MutS DNA Mismatch-Binding Protein / Q000737:chemistry*; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D014461:Ultracentrifugation
chemical_list: D003432:Cross-Linking Reagents; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C074770:MutL protein, E coli; D000255:Adenosine Triphosphate; D004706:Endodeoxyribonucleases; C059682:methyl-directed mismatch repair protein, E coli; D000251:Adenosine Triphosphatases; D000070956:MutL Proteins; D051719:MutS DNA Mismatch-Binding Protein; D045643:DNA Repair Enzymes; D003545:Cysteine