EC Number   |
General Information |
Reference |
|---|
  2.1.1.218 | evolution |
aside from an active site aspartate residue, alignment of the available Trm10 protein structures and their primary sequences show no other obvious amino acid candidates in the active site that could account for the differences between m1G9-specific (Saccharomyces cerevisiae and Schizosaccharomyces pombe), m1A9-specific (Sulfolobus acidocaldarius) and m1A9/m1G9 dual-specific (human Trmt10C and Trm10 from Thermococcus kodakarensis) Trm10 MTases. It is possible that the purine specificity might simply be due to differences in surface charge around the active site and size and/or layout of the purine-binding pocket, which could allow different Trm10 family members to accommodate different purine substrates, rather than to specific residues for catalysis. The active site pocket is more open for the m1G9-specific Trmt10A and m1A9-specific Trm10, compared to the other Trm10 proteins. No obvious similarities are observed within the m1G9-specific group of proteins that are also clearly different from the m1A9-specific Trm10, and altered in the m1G9/m1A9 dual-specific protein |
-, 756160 |
| 2.1.1.218 | evolution |
the enzyme belongs to the tRNA m1R9 methyltransferase (Trm10) family, which is conserved throughout eukarya and archaea. Distinct substrate specificities of the human tRNA methyltransferases TRMT10A and TRMT10B. hTRMT10A and hTRMT10B are not biochemically redundant. hTRMT10A is the de facto methyltransferase responsible for all m1G9 formation on cytosolic tRNA, and hTRMT10B has a much more limited and specific role in tRNA processing in humans |
758328 |
| 2.1.1.218 | malfunction |
mutation of catalytic residue Asp184 abolishes m1A9 activity in the archaeal Trm10 protein |
-, 756160 |
| 2.1.1.218 | malfunction |
mutation of catalytic residue Asp206 abolishes m1A9 activity in the archaeal Trm10 protein |
-, 756160 |
| 2.1.1.218 | metabolism |
the methylation on the N1 atom of adenosine to form 1-methyladenosine (m1A) has been identified at nucleotide position 9, 14, 22, 57, and 58 in different tRNAs. In some cases, these modifications have been shown to increase tRNA structural stability and induce correct tRNA folding. The m1A9 MTases belong to the Trm10 subfamily of the SPOUT superfamily. In addition to the m1A9 modification, the Trm10 subfamily of MTases methylates guanosine in some organisms |
-, 756160 |
| 2.1.1.218 | more |
in human Trmt10C, the catalytic aspartate residue, found in archaeal m1A9 MTases, is replaced by leucine that, due to its uncharged nature, is likely to act differently in catalysis than a charged aspartate residue. Another aspartate residue is located deep in the active site pocket of human Trmt10C (Asp293) and might be involved in catalysis, but seems unlikely to be the determinant for m1A9 activity, as this position is occupied by aspartate in the m1G9-specific Trm10 proteins from yeast, and is not conserved in m1A9 active Trm10 proteins from Sulfolobus acidocaldarius and Thermococcus kodakarensis. tRNA recognition by Trm10 enzymes, overview |
756160 |
| 2.1.1.218 | more |
purified hTRMT10B lacks m1G9 methyltransferase activity with several tested Saccharomyces cerevisiae and human tRNA substrates |
758328 |
| 2.1.1.218 | more |
residue G202 is important for catalytic activity regardless of the target purine of the tRNA species to be modified |
-, 756865 |
| 2.1.1.218 | more |
tRNA binding and adenosine N1-methylation by an archaeal Trm10 homologue, structure-function analysis, overview. N1-adenosine methylation by SaTrm10 requires two catalytic aspartate residues |
-, 757838 |
| 2.1.1.218 | more |
tRNA recognition by Trm10 enzymes, overview |
-, 756160 |
