Probing the DNA-binding center of the MutL protein from the Escherichia coli mismatch repair system via crosslinking and F örster resonance energy transfer.

Probing the DNA-binding center of the MutL protein from the Escherichia coli mismatch repair system via crosslinking and Förster resonance energy transfer. Biochimie. 2020 Feb 13;: Authors: Monakhova M, Ryazanova A, Kunetky V, Li P, Shilkin E, Kisil O, Rao DN, Oretskaya T, Friedhoff P, Kubareva E Abstract As no crystal structure of full-size MutL bound to DNA has been obtained up to date, in the present work we used crosslinking and Förster resonance energy transfer (FRET) assays for probing the putative DNA-binding center of MutL from Escherichia coli. Several single-cysteine MutL variants (scMutL) were used for site-specific crosslinking or fluorophore modification. The crosslinking efficiency between scMutL proteins and mismatched DNA modified with thiol-reactive probes correlated with the distances from the Cys residues to the DNA calculated from a model of MutS-MutL-DNA complex. FRET-based investigation of DNA-binding with different scMutL variants clearly showed the highest signals were detected for the variants MutL(T218C) and MutL(A251C) indicating closeness of the positions 218 and 251 to DNA in the MutL-DNA complex. Indeed, the Cys218 and Cys251 of scMutL were crosslinked to the reactive DNA with the highest yield demonstrating their proximity to DNA in the MutL-DNA complex. The presence of MutS increased the yield of conjugate formation between the MutL variants and the modified DNA due to tighter MutL-DNA interactions caused by MutS...
Source: Biochimie - Category: Biochemistry Authors: Tags: Biochimie Source Type: research

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Source: Biomed Res - Category: Research Authors: Tags: Biomed Res Int Source Type: research
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Source: IUBMB Life - Category: Research Authors: Tags: SPECIAL ISSUE Source Type: research
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Source: International Journal of Biological Macromolecules - Category: Biochemistry Authors: Tags: Int J Biol Macromol Source Type: research
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Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
AbstractThe family of AlkB homolog (ALKBH) proteins, the homologs ofEscherichia coli AlkB 2 ‐oxoglutarate (2OG), and Fe(II)‐dependent dioxygenase are involved in a number of important regulatory processes in eukaryotic cells including repair of alkylation lesions in DNA, RNA, and nucleoprotein complexes. There are nine human and thirteenArabidopsis thaliana ALKBH proteins described, which exhibit diversified functions. Among them, human ALKBH5 and FaT mass and Obesity ‐associated (FTO) protein and Arabidopsis ALKBH9B and ALKBH10B have been recognized as N6 methyladenine (N6meA) demethylases, the most abundant posttra...
Source: IUBMB Life - Category: Research Authors: Tags: SPECIAL ISSUE Source Type: research
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Source: Biomed Res - Category: Research Authors: Tags: J Biomed Mater Res A Source Type: research
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