5 articles
DNA adenine methylase
DNA adenine methylase (Dam) is the bacterial GATC-specific N6-adenine methyltransferase of E. coli, an orphan enzyme regulating replication, mismatch repair, and virulence gene expression via epigenetic methylation.
DNA Cytosine-5 Methyltransferase
DNA (cytosine-5)-methyltransferases (EC 2.1.1.37; DNMT1, DNMT3A, DNMT3B) are SAM-dependent enzymes that methylate cytosine C5, mostly at CpG sites, establishing (de novo) and maintaining epigenetic methylation patterns; DNMT2/TRDMT1 methylates tRNA instead.
DNA methyltransferase
DNA methyltransferases (DNMT1, DNMT3A/3B, DNMT3L, DNMT2) are SAM-dependent enzymes that methylate cytosine C5, maintaining and establishing DNA methylation; DNMT2 acts on tRNA, and DNMT inhibitors like decitabine are FDA-approved cancer drugs.
DNA methyltransferase 3A
DNA methyltransferase 3A (DNMT3A), a de novo cytosine-5 DNA methyltransferase on chromosome 2p23, establishes methylation patterns in development; its ADD-domain autoinhibition, R882 mutations in AML and clonal hematopoiesis, and Tatton-Brown-Rahman overgrowth syndrome distinguish it.
Restriction endonuclease, type I, methylase subunit
HsdM is the methyltransferase (M) subunit of type I restriction-modification enzymes, encoded by hsdM. Two HsdM plus HsdS methylate adenines (m6A) via base flipping using AdoMet; motifs I and IV handle cofactor binding and catalysis.