The methylase that is responsible for autoimmunity in the thiostrepton producer Streptomyces azureus, renders ribosomes completely resistant to thiostrepton .
The expected taxonomic range for this enzyme is: Bacteria, Eukaryota
The methylase that is responsible for autoimmunity in the thiostrepton producer Streptomyces azureus, renders ribosomes completely resistant to thiostrepton [2].
Substrates: as 58 nucleotide substrate for methylation, or as shortened 29 nt hairpin substrate, local base-base interactions play an important role in aligning the substrate 2'-hydroxyl group of A1067 for methyl group transfer, stoichiometry of RNA binding by the NHR dimer, overview Products: -
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S-adenosyl-L-methionine + adenosine1067 in 23S rRNA
S-adenosyl-L-homocysteine + 2'-O-methyladenosine1067 in 23S rRNA
Substrates: 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 tthiostrepton Products: -
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S-adenosyl-L-methionine + adenosine1067 in 23S rRNA
S-adenosyl-L-homocysteine + 2'-O-methyladenosine1067 in 23S rRNA
Substrates: the methylase enzyme, responsible for autoimmunity in the thiostrepton producer Streptomyces azureus, renders ribosomes completely resistant to thiostrepton Products: -
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S-adenosyl-L-methionine + adenosine1067 in 23S rRNA
S-adenosyl-L-homocysteine + 2'-O-methyladenosine1067 in 23S rRNA
Substrates: RNA sequence variants of the RNA fragment with mutations in nucleotides 1051-1108 are tested as substrates for the methylase. Methylation is dependent on the secondary structure of the hairpin including nucleotide A1067 and the exact sequence U(1066)-A(1067)-G(1068)-A(1O69)-A(1070) of the single strand Products: -
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S-adenosyl-L-methionine + adenosine1067 in 23S rRNA
S-adenosyl-L-homocysteine + 2'-O-methyladenosine1067 in 23S rRNA
Substrates: enzyme Tsr uses the co-substrate AdoMet to methylate the 23 S rRNA, presumably prior to the assembly of the 50 S subunit as the L11 and proposed Tsr binding surfaces are overlapping Products: -
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S-adenosyl-L-methionine + adenosine1067 in 23S rRNA
S-adenosyl-L-homocysteine + 2'-O-methyladenosine1067 in 23S rRNA
Substrates: compared the methylation activity of the Arg135Ala NHR heterodimer with the wild-type NHR homodimer and a series of 29 nt wild-type and mutant RNA substrates. The inactive heterodimer complex binds the RNA more efficiently than the inactive mutant homodimer. Construction of diverse mutant RNA substrates in which A1067 is replaced by adenine structural analogues, A1067G retains significant activity, while 7-deaza-A and 1-methyl-A substitutions at A1067 reduce the activity, overview Products: -
Substrates: compared the methylation activity of the Arg135Ala NHR heterodimer with the wild-type NHR homodimer and a series of 29 nt wild-type and mutant RNA substrates. The inactive heterodimer complex binds the RNA more efficiently than the inactive mutant homodimer. Construction of diverse mutant RNA substrates in which A1067 is replaced by adenine structural analogues, A1067G retains significant activity, while 7-deaza-A and 1-methyl-A substitutions at A1067 reduce the activity, overview Products: -
Substrates: 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 tthiostrepton Products: -
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S-adenosyl-L-methionine + adenosine1067 in 23S rRNA
S-adenosyl-L-homocysteine + 2'-O-methyladenosine1067 in 23S rRNA
Substrates: the methylase enzyme, responsible for autoimmunity in the thiostrepton producer Streptomyces azureus, renders ribosomes completely resistant to thiostrepton Products: -
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S-adenosyl-L-methionine + adenosine1067 in 23S rRNA
S-adenosyl-L-homocysteine + 2'-O-methyladenosine1067 in 23S rRNA
Substrates: enzyme Tsr uses the co-substrate AdoMet to methylate the 23 S rRNA, presumably prior to the assembly of the 50 S subunit as the L11 and proposed Tsr binding surfaces are overlapping Products: -
stabilizing the RNA tertiary structure, as in RNA mutant U1061A, decreases Tsr binding affinity and catalytic activity independent of RNA structural changes
stabilizing the RNA tertiary structure, as in RNA mutant U1061A, decreases Tsr binding affinity and catalytic activity independent of RNA structural changes
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
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
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
the methylase enzyme, responsible for autoimmunity in the thiostrepton producer Streptomyces azureus, renders ribosomes completely resistant to thiostrepton
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
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
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
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
each protomer 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, Tsr domain organization, overview
site-directed mutagenesis, the mutant is unable to promote the RNase V1-sensitive RNA structural changes, but maintains its interaction with the RNA under certain conditions for the protection of nucleotides G1068 and G1071 from cleavage by RNase T1
site-directed mutagenesis, the inactive R135A mutant homodimer binds to the RNA causing a shift in electrophoretic mobility, and the heterodimer composed of active and inactive subunits also binds the RNA efficiently. The inactive heterodimer complex binds the RNA more efficiently than the inactive mutant homodimer
recombinant His-tagged enzyme from Escherichia coli strain BL21(DE3)-pLysS by nickel affinity and heparin affinity chromatography, followed by gel filtration
Overexpression of the thiostrepton-resistance gene from Streptomyces azureus in Escherichia coli and characterization of recognition sites of the 23S rRNA A1067 2'-methyltransferase in the guanosine triphosphatase center of 23S ribosomal RNA