Summary: CheR methyltransferase, all-alpha domain

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Protein-glutamate O-methyltransferase Edit Wikipedia article

protein-glutamate O-methyltransferase

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PubMed	articles
NCBI	proteins

CheR methyltransferase, all-alpha domain

chemotaxis receptor recognition by protein methyltransferase cher

Identifiers

Symbol

CheR_N

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe
PDBsum	structure summary

CheR methyltransferase, SAM binding domain

chemotaxis receptor recognition by protein methyltransferase cher

Identifiers

Symbol

CheR

Pfam clan

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe
PDBsum	structure summary

In enzymology, a protein-glutamate O-methyltransferase (EC 2.1.1.80) is an enzyme that catalyzes the chemical reaction

S-adenosyl-L-methionine + protein L-glutamate $\rightleftharpoons$ S-adenosyl-L-homocysteine + protein L-glutamate methyl ester

Thus, the two substrates of this enzyme are S-adenosyl methionine and protein L-glutamic acid, whereas its two products are S-adenosylhomocysteine and protein L-glutamate methyl ester.

This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:protein-L-glutamate O-methyltransferase. Other names in common use include methyl-accepting chemotaxis protein O-methyltransferase, S-adenosylmethionine-glutamyl methyltransferase, methyl-accepting chemotaxis protein methyltransferase II, S-adenosylmethionine:protein-carboxyl O-methyltransferase, protein methylase II, MCP methyltransferase I, MCP methyltransferase II, protein O-methyltransferase, protein(aspartate)methyltransferase, protein(carboxyl)methyltransferase, protein carboxyl-methylase, protein carboxyl-O-methyltransferase, protein carboxylmethyltransferase II, protein carboxymethylase, protein carboxymethyltransferase, and protein methyltransferase II. This enzyme participates in bacterial chemotaxis - general and bacterial chemotaxis - organism-specific.

CheR proteins are part of the chemotaxis signaling mechanism which methylates the chemotaxis receptor at specific glutamate residues. Methyl transfer from the ubiquitous S-adenosyl-L-methionine (AdoMet/SAM) to either nitrogen, oxygen or carbon atoms is frequently employed in diverse organisms ranging from bacteria to plants and mammals. The reaction is catalysed by methyltransferases (Mtases) and modifies DNA, RNA, proteins and small molecules, such as catechol for regulatory purposes. The various aspects of the role of DNA methylation in prokaryotic restriction-modification systems and in a number of cellular processes in eukaryotes including gene regulation and differentiation is well documented.

Flagellated bacteria swim towards favourable chemicals and away from deleterious ones. Sensing of chemoeffector gradients involves chemotaxis receptors, transmembrane (TM) proteins that detect stimuli through their periplasmic domains and transduce the signals via their cytoplasmic domains .^[1] Signalling outputs from these receptors are influenced both by the binding of the chemoeffector ligand to their periplasmic domains and by methylation of specific glutamate residues on their cytoplasmic domains. Methylation is catalysed by CheR, an S-adenosylmethionine-dependent methyltransferase,^[1] which reversibly methylates specific glutamate residues within a coiled coil region, to form gamma-glutamyl methyl ester residues.^[1]^[2] The structure of the Salmonella typhimurium chemotaxis receptor methyltransferase CheR, bound to S-adenosylhomocysteine, has been determined to a resolution of 2.0 Angstrom.^[1] The structure reveals CheR to be a two-domain protein, with a smaller N-terminal helical domain linked via a single polypeptide connection to a larger C-terminal alpha/beta domain. The C-terminal domain has the characteristics of a nucleotide-binding fold, with an insertion of a small anti-parallel beta-sheet subdomain. The S-adenosylhomocysteine-binding site is formed mainly by the large domain, with contributions from residues within the N-terminal domain and the linker region.^[1]

[edit] Structural studies

As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes 1AF7 and 1BC5.

[edit] References

^ ^a ^b ^c ^d ^e Djordjevic S, Stock AM (April 1997). "Crystal structure of the chemotaxis receptor methyltransferase CheR suggests a conserved structural motif for binding S-adenosylmethionine". Structure 5 (4): 545â58. doi:10.1016/S0969-2126(97)00210-4. PMID 9115443.
^ Djordjevic S, Stock AM (June 1998). "Chemotaxis receptor recognition by protein methyltransferase CheR". Nat. Struct. Biol. 5 (6): 446â50. doi:10.1038/nsb0698-446. PMID 9628482.

[edit] Further reading

Burgess-Cassler A, Ullah AH, Ordal GW (1982). "Purification and characterization of Bacillus subtilis methyl-accepting chemotaxis protein methyltransferase II". J. Biol. Chem. 257 (14): 8412â7. PMID 6806296.
Kleene SJ, Toews ML, Adler J (1977). "Isolation of glutamic acid methyl ester from an Escherichia coli membrane protein involved in chemotaxis". J. Biol. Chem. 252 (10): 3214â8. PMID 16888.
Simms SA, Stock AM, Stock JB (1987). "Purification and characterization of the S-adenosylmethionine:glutamyl methyltransferase that modifies membrane chemoreceptor proteins in bacteria". J. Biol. Chem. 262 (18): 8537â43. PMID 3298235.
Springer WR, Koshland DE Jr (1977). "Identification of a protein methyltransferase as the cheR gene product in the bacterial sensing system". Proc. Natl. Acad. Sci. U.S.A. 74 (2): 533â7. doi:10.1073/pnas.74.2.533. PMC 392324. PMID 322131. //www.ncbi.nlm.nih.gov/pmc/articles/PMC392324/.

This article incorporates text from the public domain Pfam and InterPro IPR022641

This article incorporates text from the public domain Pfam and InterPro IPR022642

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

CheR methyltransferase, all-alpha domain Provide feedback

CheR proteins are part of the chemotaxis signaling mechanism in bacteria. CheR methylates the chemotaxis receptor at specific glutamate residues. CheR is an S-adenosylmethionine- dependent methyltransferase.

Literature references

Djordjevic S, Stock AM; , Structure 1997;5:545-558.: Crystal structure of the chemotaxis receptor methyltransferase CheR suggests a conserved structural motif for binding S-adenosylmethionine. PUBMED:9115443 EPMC:9115443

External database links

PANDIT:	PF03705
Pseudofam:	PF03705
SCOP:	1af7
SYSTERS:	CheR_N

This tab holds annotation information from the InterPro database.

InterPro entry IPR022641

CheR proteins are part of the chemotaxis signaling mechanism which methylates the chemotaxis receptor at specific glutamate residues. This entry refers to the N-terminal domain of the CherR-type MCP methyltransferases, which are found in bacteria, archaea and green plants. This entry is found in association with .

Methyl transfer from the ubiquitous S-adenosyl-L-methionine (AdoMet) to either nitrogen, oxygen or carbon atoms is frequently employed in diverse organisms ranging from bacteria to plants and mammals. The reaction is catalysed by methyltransferases (Mtases) and modifies DNA, RNA, proteins and small molecules, such as catechol for regulatory purposes. The various aspects of the role of DNA methylation in prokaryotic restriction-modification systems and in a number of cellular processes in eukaryotes including gene regulation and differentiation is well documented.

Three classes of DNA Mtases transfer the methyl group from AdoMet to the target base to form either N-6-methyladenine, or N-4-methylcytosine, or C-5- methylcytosine. In C-5-cytosine Mtases, ten conserved motifs are arranged in the same order [PUBMED:8127644]. Motif I (a glycine-rich or closely related consensus sequence; FAGxGG in M.HhaI [PUBMED:8343957]), shared by other AdoMet-Mtases [PUBMED:2684970], is part of the cofactor binding site and motif IV (PCQ) is part of the catalytic site. In contrast, sequence comparison among N-6-adenine and N-4-cytosine Mtases indicated two of the conserved segments [PUBMED:2690010], although more conserved segments may be present. One of them corresponds to motif I in C-5-cytosine Mtases, and the other is named (D/N/S)PP(Y/F). Crystal structures are known for a number of Mtases [PUBMED:7607476, PUBMED:8343957, PUBMED:8127644, PUBMED:7971991]. The cofactor binding sites are almost identical and the essential catalytic amino acids coincide. The comparable protein folding and the existence of equivalent amino acids in similar secondary and tertiary positions indicate that many (if not all) AdoMet-Mtases have a common catalytic domain structure. This permits tertiary structure prediction of other DNA, RNA, protein, and small-molecule AdoMet-Mtases from their amino acid sequences [PUBMED:7897657].

Flagellated bacteria swim towards favourable chemicals and away from deleterious ones. Sensing of chemoeffector gradients involves chemotaxis receptors, transmembrane (TM) proteins that detect stimuli through their periplasmic domains and transduce the signals via their cytoplasmic domains [PUBMED:9115443]. Signalling outputs from these receptors are influenced both by the binding of the chemoeffector ligand to their periplasmic domains and by methylation of specific glutamate residues on their cytoplasmic domains. Methylation is catalysed by CheR, an S-adenosylmethionine-dependent methyltransferase [PUBMED:9115443], which reversibly methylates specific glutamate residues within a coiled coil region, to form gamma-glutamyl methyl ester residues [PUBMED:9115443, PUBMED:9628482]. The structure of the Salmonella typhimurium chemotaxis receptor methyltransferase CheR, bound to S-adenosylhomocysteine, has been determined to a resolution of 2.0 A [PUBMED:9115443]. The structure reveals CheR to be a two-domain protein, with a smaller N-terminal helical domain linked via a single polypeptide connection to a larger C-terminal alpha/beta domain. The C-terminal domain has the characteristics of a nucleotide-binding fold, with an insertion of a small anti-parallel beta-sheet subdomain. The S-adenosylhomocysteine-binding site is formed mainly by the large domain, with contributions from residues within the N-terminal domain and the linker region [PUBMED:9115443].

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Alignments

We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the NCBI sequence database, and our metagenomics sequence database. More...

There are various ways to view or download the sequence alignments that we store. We provide several sequence viewers and a plain-text Stockholm-format file for download.

Alignment types

We make a range of alignments for each Pfam-A family:

seed: the curated alignment from which the HMM for the family is built
full: the alignment generated by searching the sequence database using the HMM
RP15/RP35/RP55/RP75: Representative Proteomes (RPs) at 15%, 35%, 55% and 75% co-membership thresholds
NCBI: alignment generated by searching the NCBI sequence database using the family HMM
meta: alignment generated by searching the metagenomics sequence database using the family HMM

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We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.

	Seed (77)	Full (3379)	Representative proteomes				NCBI (2654)	Meta (197)
	Seed (77)	Full (3379)	RP15 (348)	RP35 (678)	RP55 (867)	RP75 (1043)	NCBI (2654)	Meta (197)
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¹Cannot generate PP/Heatmap alignments for seeds; no PP data available

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Format an alignment

	Seed (77)	Full (3379)	Representative proteomes				NCBI (2654)	Meta (197)
	Seed (77)	Full (3379)	RP15 (348)	RP35 (678)	RP55 (867)	RP75 (1043)	NCBI (2654)	Meta (197)
Alignment:
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Order:	Tree Alphabetical
Sequence:	Inserts lower case All upper case
Gaps:
Download/view:	Download View

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We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

	Seed (77)	Full (3379)	Representative proteomes				NCBI (2654)	Meta (197)
	Seed (77)	Full (3379)	RP15 (348)	RP35 (678)	RP55 (867)	RP75 (1043)	NCBI (2654)	Meta (197)
Raw Stockholm	Download	Download	Download	Download	Download	Download	Download	Download
Gzipped	Download	Download	Download	Download	Download	Download	Download	Download

You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

External links

MyHits provides a collection of tools to handle multiple sequence alignments. For example, one can refine a seed alignment (sequence addition or removal, re-alignment or manual edition) and then search databases for remote homologs using HMMER3.

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Trees

This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

Note: You can also download the data file for the tree.

Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation

Seed source:

Pfam-B_694 (release 4.2)

Previous IDs:

none

Type:

Domain

Author:

Bateman A, Griffiths-Jones SR

Number in seed:

77

Number in full:

3379

Average length of the domain:

56.40 aa

Average identity of full alignment:

24 %

Average coverage of the sequence by the domain:

14.23 %

HMM information

HMM build commands:

build method: hmmbuild -o /dev/null HMM SEED

search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq

Model details:

Parameter	Sequence	Domain
Gathering cut-off	20.8	20.8
Trusted cut-off	20.8	20.8
Noise cut-off	20.7	20.7

Model length:

57

Family (HMM) version:

10

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Species distribution

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This chart is a modified "sunburst" visualisation of the species tree for this family. It shows each node in the tree as a separate arc, arranged radially with the superkingdoms at the centre and the species arrayed around the outermost ring.

How the sunburst is generated

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Unmapped species names

The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.

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Unfortunately we have found that there are problems viewing the interactive tree when the it becomes larger than a certain limit. Furthermore, we have found that Internet Explorer can become unresponsive when viewing some trees, regardless of their size. We therefore show a text representation of the species tree when the size is above a certain limit or if you are using Internet Explorer to view the site.

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Interactive tree

For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.

We also count the number of unique sequences on which each domain is found, which is shown in green. Note that a domain may appear multiple times on the same sequence, leading to the difference between these two numbers.

Finally, we group sequences from the same organism according to the NCBI code that is assigned by UniProt, allowing us to count the number of distinct sequences on which the domain is found. This value is shown in the pink boxes.

We use the NCBI species tree to group organisms according to their taxonomy and this forms the structure of the displayed tree. Note that in some cases the trees are too large (have too many nodes) to allow us to build an interactive tree, but in most cases you can still view the tree in a plain text, non-interactive representation. Those species which are represented in the seed alignment for this domain are highlighted.

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Interactions

There is 1 interaction for this family. More...

CheR

Structures

For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the CheR_N domain has been found. There are 2 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.

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Archea	Eukaryota
Bacteria	Other sequences
Viruses	Unclassified
Viroids	Unclassified sequence

Family: CheR_N (PF03705)

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Summary: CheR methyltransferase, all-alpha domain

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Protein-glutamate O-methyltransferase Edit Wikipedia article

[edit] Structural studies

[edit] References

[edit] Further reading

CheR methyltransferase, all-alpha domain Provide feedback

Literature references

External database links

InterPro entry IPR022641

Domain organisation

Alignments

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Curation and family details

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