2.1.1.230	malfunction	in the absence of the N-terminal domain, Tsr is catalytically inactive despite possessing the intact S-adenosyl-L-methionine binding sites and catalytic center. The Tsr-C-terminal domain dimer binds the RNA 30fold more weakly than the wild-type enzyme and is unable to promote the N-terminal domain-dependent RNA conformational change	736455	
2.1.1.230	additional information	each protomer of the homodimer containing an L30e-like amino-terminal domain and a SPOUT methyltransferase family catalytic carboxyl-terminal domain, both enzyme domains are required for high affinity RNA substrate binding. The Tsr-C-terminal domain has intrinsic, weak RNA affinity that is necessary to direct the specific high-affinity Tsr-RNA interaction via N-terminal domains, which have no detectable RNA affinity when isolated. The N-terminal domains increase RNA binding affinity and are necessary for catalysis, RNA binding mechanism, overview. The N-terminal domain of Tsr is an essential component of the RNA substrate recognition mechanism by both promoting high affinity RNA binding and activation of catalysis by the C-terminal domain	736455	
2.1.1.230	additional information	the NHR heterodimer requires only one functional subunit for RNA recognition and enzymatic activity. The catalytic residue is Arg135	737073	
2.1.1.230	physiological function	methylation at adenosine1067 in 23S rRNA is essential for resistance against nosiheptide, a sulfur peptide antibiotic, which is produced by the nosiheptide-producing strain, Streptomyces actuosus	711257	
2.1.1.230	physiological function	Streptomyces azureus is the producer of the peptide antibiotic thiostrepton. Thiostrepton inhibits protein synthesis by binding to the complex of 23S rRNA and protein L-11 which blocks processes associated with the GTP-hydrolysis center of the ribosome including the binding of guanine nucleotides, elongation factor proteins and tRNA. 23S rRNA (adenosine1067-2'-O)-methyltransferase confers resistance to thiostrepton	485514	
2.1.1.230	physiological function	the enzyme is involved in resistance to thiostrepton	485512	
2.1.1.230	physiological function	the methylase enzyme, responsible for autoimmunity in the thiostrepton producer Streptomyces azureus, renders ribosomes completely resistant to thiostrepton	485513	
2.1.1.230	physiological function	the nosiheptide producer Streptomyces actuosis prevents self-intoxication by expressing the enzyme, which methylates the 2'-hydroxyl of 23 S rRNA nucleotide adenosine 1067 within the antibiotic binding site. Methylation at A1067 blocks thiazole binding directly. This region of 23S rRNA is also the binding site for the ribosomal protein L11	737073	
2.1.1.230	physiological function	the thiostrepton producer Streptomyces azureus prevents self-intoxication by expressing the thiostrepton-resistance methyltransferase (Tsr), which methylates the 2'-hydroxyl of 23 S rRNA nucleotide adenosine 1067 within the thiostrepton binding site	736455