Any feedback?
No. of entries
Information on EC 2.1.1.176 - 16S rRNA (cytosine967-C5)-methyltransferase
for references in articles please use BRENDA:EC2.1.1.176
Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
EC Tree 2 Transferases
2.1 Transferring one-carbon groups
2.1.1 Methyltransferases
2.1.1.176 16S rRNA (cytosine967-C5)-methyltransferase
IUBMB Comments
The enzyme specifically methylates cytosine967 at C5 in 16S rRNA.
The expected taxonomic range for this enzyme is: Bacteria, Eukaryota, Archaea
Reaction Schemes
show+
=
+
+
cytosine967 in 16S rRNA
=
+
5-methylcytosine967 in 16S rRNA
Synonyms
fmu/rsmb/rrmb, ph0851, rna:m5c mtase, more
topPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
16S rRNA methyltransferase
fmu
Fmu/RsmB/RrmB
Fmu/RsmB/RrmB rRNA cytosine 5-methyltransferase
RNA:m5C MTase
rsmB
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
S-adenosyl-L-methionine + cytosine967 in 16S rRNA = S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
S-adenosyl-L-methionine + cytosine967 in 16S rRNA = S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
-
-
-
-
S-adenosyl-L-methionine + cytosine967 in 16S rRNA = S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
a model for the reaction mechanism is proposed
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
SYSTEMATIC NAME
IUBMB Comments
S-adenosyl-L-methionine:16S rRNA (cytosine967-C5)-methyltransferase
The enzyme specifically methylates cytosine967 at C5 in 16S rRNA.
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
-
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
Substrates: the recombinant protein exhibits the same specificity as the native enzyme. It forms only m5C and only at position 967. C1407, which is also 5-methylcytosine in natural 16S RNA, is not methylated. In vitro, the enzyme only recognizes free 16S RNA. 30S ribosomal subunits are not a substrate
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
-
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
-
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
-
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
Substrates: -
Products: -
Products: -
?
additional information
?
-
-
Substrates: substrate recognition mechanism, overview
Products: -
Products: -
?
additional information
?
-
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
Substrates: substrate recognition mechanism, overview
Products: -
Products: -
?
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
-
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
-
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
-
Substrates: -
Products: -
Products: -
?
S-adenosyl-L-methionine + cytosine967 in 16S rRNA
S-adenosyl-L-homocysteine + 5-methylcytosine967 in 16S rRNA
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
Substrates: -
Products: -
Products: -
?
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
additional information
no requirement for added Mg2+, suggesting that extensive secondary or tertiary structure in the RNA substrate may not be a requirement for recognition
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
7.5
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
37
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
Highest Expressing Human Cell Lines
Cell Line LinksPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
evolution
malfunction
metabolism
additional information
evolution
Fmu/RsmB/RrmB homologues exist not only in bacteria but also in archaea and eukarya and constitute a large orthologous group in the RNA:m5C methyltransferase family. The sequence of the N-terminal domain is negligibly conserved between the bacterial and archaeal subfamilies
evolution
-
Fmu/RsmB/RrmB homologues exist not only in bacteria but also in archaea and eukarya and constitute a large orthologous group in the RNA:m5C methyltransferase family. The sequence of the N-terminal domain is negligibly conserved between the bacterial and archaeal subfamilies
malfunction
-
deletion of rsmB in a C-terminal S9 tail deletion strain of Escherichia coli causes significantly increased -1 frameshifting at 37°C
malfunction
-
deletion of rsmB in a C-terminal S9 tail deletion strain of Escherichia coli causes significantly increased -1 frameshifting at 37°C
-
metabolism
-
two methyltransferases, RsmB and RsmF, are responsible for all four 5-methylcytidine modifications in 16S rRNA of Thermus thermophilus, overview. RsmB produces m5C967, while RsmF methylates C1400, C1404, and C1407 in a 30S subunit substrate, but only C1400 and C1404 when naked 16S rRNA is the substrate
metabolism
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
two methyltransferases, RsmB and RsmF, are responsible for all four 5-methylcytidine modifications in 16S rRNA of Thermus thermophilus, overview. RsmB produces m5C967, while RsmF methylates C1400, C1404, and C1407 in a 30S subunit substrate, but only C1400 and C1404 when naked 16S rRNA is the substrate
-
additional information
next to the S-adenosyl-L-methionine-binding site is a positively charged cleft, formed between the N- and C-terminal domains, which is conserved in the archaeal PH0851 homologues and seems to be suitable for binding the RNA substrate
additional information
-
next to the S-adenosyl-L-methionine-binding site is a positively charged cleft, formed between the N- and C-terminal domains, which is conserved in the archaeal PH0851 homologues and seems to be suitable for binding the RNA substrate
Show AA Sequence and Transmembrane Helices (10205 entries)
Longer loading times are possible. Please use the AA Sequence and Transmembrane Helices Search for a specific query.
Longer loading times are possible. Please use the AA Sequence and Transmembrane Helices Search for a specific query.
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
monomer
two domains and one linker: an N-terminal domain formed by residues 1-145, a C-terminal domain formed by residues 185-448, and an alpha-helical linker formed by residues 146-184
additional information
additional information
-
next to the S-adenosyl-L-methionine-binding site is a positively charged cleft, formed between the N- and C-terminal domains, that seems to be suitable for binding the RNA substrate. The N-terminal domains of Pyrococcus horikoshii PH0851 and Escherichia coli Fmu/RsmB/RrmB are both alpha-helical and adopt a similar topology, sequence and structure comparison, overview
additional information
next to the S-adenosyl-L-methionine-binding site is a positively charged cleft, formed between the N- and C-terminal domains, which is conserved in the archaeal PH0851 homologues and seems to be suitable for binding the RNA substrate. The N-terminal domains of Pyrococcus horikoshii PH0851 and Escherichia coli Fmu/RsmB/RrmB are both alpha-helical and adopt a similar topology, sequence and structure comparison, overview
additional information
-
next to the S-adenosyl-L-methionine-binding site is a positively charged cleft, formed between the N- and C-terminal domains, which is conserved in the archaeal PH0851 homologues and seems to be suitable for binding the RNA substrate. The N-terminal domains of Pyrococcus horikoshii PH0851 and Escherichia coli Fmu/RsmB/RrmB are both alpha-helical and adopt a similar topology, sequence and structure comparison, overview
additional information
-
comparison of Thermus thermophilus RsmB and RsmF protein sequences, secondary and tertiary structure, differences in substrate binding, overview
additional information
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
comparison of Thermus thermophilus RsmB and RsmF protein sequences, secondary and tertiary structure, differences in substrate binding, overview
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
hanging-drop vapor diffusion method, crystal structure of Escherichia coli Fmu, determined at 1.65 A resolution for the apoenzyme and 2.1 A resolution in complex with S-adenosyl-L-methionine
purified wild-type and SeMet-labeled PH0851 complexed with S-adenosyl-L-methionine-analogue sinefungin, hanging drop vapour diffusion method, mixing of protein solution, containing 1.7 mg/ml protein in 20 mM Tris-HCl buffer, pH 8.0, 400 mM NaCl, and 1 mM sinefungin, with reservoir solution, containing 80 mM HEPES-Na buffer, pH 7.0, 1.15 M sodium citrate, and 7-15% w/v 1,6-hexanediol, in a 4:1 ratio, 20°C, 1 week, X-ray diffraction structure determination and analysis at 2.55-3.0 A resolution, molecular replacement
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
additional information
additional information
-
construction of a null mutant strain in which TTHA0851 is inactivated by homologous recombination and insertion of a heat stable kanamycin-resistance gene
additional information
Thermus thermophilus HB8 / ATCC 27634 / DSM 579
-
construction of a null mutant strain in which TTHA0851 is inactivated by homologous recombination and insertion of a heat stable kanamycin-resistance gene
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Tscherne, J.S.; Nurse, K.; Popienick, P.; Michel, H.; Sochacki, M.; Ofengand, J.
Purification, cloning, and characterization of the 16S RNA m5C967 methyltransferase from Escherichia coli
Biochemistry
38
1884-1892
1999
Escherichia coli (P36929)
brenda
Gu, X.R.; Gustafsson, C.; Ku, J.; Yu, M.; Santi, D.V.
Identification of the 16S rRNA m5C967 methyltransferase from Escherichia coli
Biochemistry
38
4053-4057
1999
Escherichia coli (P36929), Escherichia coli
brenda
Foster, P.G.; Nunes, C.R.; Greene, P.; Moustakas, D.; Stroud, R.M.
The first structure of an RNA m5C methyltransferase, Fmu, provides insight into catalytic mechanism and specific binding of RNA substrate
Structure
11
1609-1620
2003
Escherichia coli (P36929), Escherichia coli
brenda
Hikida, Y.; Kuratani, M.; Bessho, Y.; Sekine, S.I.; Yokoyama, S.
Structure of an archaeal homologue of the bacterial Fmu/RsmB/RrmB rRNA cytosine 5-methyltransferase
Acta Crystallogr. Sect. D
66
1301-1307
2010
Escherichia coli, Pyrococcus horikoshii (O58581), Pyrococcus horikoshii
brenda
Demirci, H.; Larsen, L.H.; Hansen, T.; Rasmussen, A.; Cadambi, A.; Gregory, S.T.; Kirpekar, F.; Jogl, G.
Multi-site-specific 16S rRNA methyltransferase RsmF from Thermus thermophilus
RNA
16
1584-1596
2010
Thermus thermophilus, Thermus thermophilus HB8 / ATCC 27634 / DSM 579
brenda
Arora, S.; Bhamidimarri, S.P.; Weber, M.H.; Varshney, U.
Role of the ribosomal P-site elements of m2G966, m5C967, and the S9 C-terminal tail in maintenance of the reading frame during translational elongation in Escherichia coli
J. Bacteriol.
195
3524-3530
2013
Escherichia coli, Escherichia coli BW25113
brenda
Arora, S.; Bhamidimarri, S.P.; Bhattacharyya, M.; Govindan, A.; Weber, M.H.; Vishveshwara, S.; Varshney, U.
Distinctive contributions of the ribosomal P-site elements m2G966, m5C967 and the C-terminal tail of the S9 protein in the fidelity of initiation of translation in Escherichia coli
Nucleic Acids Res.
41
4963-4975
2013
Escherichia coli
brenda
Prokhorova, I.V.; Osterman, I.A.; Burakovsky, D.E.; Serebryakova, M.V.; Galyamina, M.A.; Pobeguts, O.V.; Altukhov, I.; Kovalchuk, S.; Alexeev, D.G.; Govorun, V.M.; Bogdanov, A.A.; Sergiev, P.V.; Dontsova, O.A.
Modified nucleotides m2G966/m5C967 of Escherichia coli 16S rRNA are required for attenuation of tryptophan operon
Sci. Rep.
3
3236
2013
Escherichia coli, Escherichia coli BW25113
brenda
EXTERNAL LINKS (specific for EC-Number 2.1.1.176)
html completed
Use of this online version of BRENDA is free under the CC BY 4.0 license. See terms of use for full details.
Release 2026.1 (March 2026)
About BRENDA
Social media
Help
Survey
Download
Contribution
Legal
Curated at
Member of
![DSMZ Digital Diversity]()
![Global Core Biodata Resource]()
![ELIXIR Core Data Resource]()
![German Network for Bioinformatics Infrastructure]()
