Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
4  structures 1959  species 2  interactions 3655  sequences 120  architectures

# Summary: CheB methylesterase

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

This is the Wikipedia entry entitled "Protein-glutamate methylesterase". More...

# Protein-glutamate methylesterase

protein-glutamate methylesterase
Identifiers
EC number 3.1.1.61
CAS number 93792-01-9
Databases
IntEnz IntEnz view
BRENDA BRENDA entry
ExPASy NiceZyme view
KEGG KEGG entry
MetaCyc metabolic pathway
PRIAM profile
PDB structures RCSB PDB PDBe PDBsum
Gene Ontology AmiGO / EGO
CheB_methylest

structural basis for methylesterase cheb regulation by a phosphorylation-activated domain
Identifiers
Symbol CheB_methylest
Pfam PF01339
InterPro IPR000673
SCOP 1chd
SUPERFAMILY 1chd

In enzymology, a protein-glutamate methylesterase (EC 3.1.1.61) is an enzyme that catalyzes the chemical reaction

protein L-glutamate O5-methyl ester + H2O $\rightleftharpoons$ protein L-glutamate + methanol

Thus, the two substrates of this enzyme are protein L-glutamate O5-methyl ester and H2O, whereas its two products are protein L-glutamate and methanol.

This enzyme is a demethylase, and more specifically it belongs to the family of hydrolases, specifically those acting on carboxylic ester bonds. The systematic name of this enzyme class is protein-L-glutamate-O5-methyl-ester acylhydrolase. Other names in common use include chemotaxis-specific methylesterase, methyl-accepting chemotaxis protein methyl-esterase, CheB methylesterase, methylesterase CheB, protein methyl-esterase, protein carboxyl methylesterase, PME, protein methylesterase, and protein-L-glutamate-5-O-methyl-ester acylhydrolase. This enzyme participates in 3 metabolic pathways: two-component system - general, bacterial chemotaxis - general, and bacterial chemotaxis - organism-specific.

CheB is part of a two-component signal transduction system. These systems enable bacteria to sense, respond, and adapt to a wide range of environments, stressors, and growth conditions.[1] Two-component systems are composed of a sensor histidine kinase (HK) and its cognate response regulator (RR).[2] The HK catalyses its own autophosphorylation followed by the transfer of the phosphoryl group to the receiver domain on RR; phosphorylation of the RR usually activates an attached output domain, in this case a methyltransferase domain.

CheB is involved in chemotaxis. CheB methylesterase is responsible for removing the methyl group from the gamma-glutamyl methyl ester residues in the methyl-accepting chemotaxis proteins (MCP). CheB is regulated through phosphorylation by CheA. The N-terminal region of the protein is similar to that of other regulatory components of sensory transduction systems.

## Structural studies

As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes 1A2O and 1CHD.

## References

1. ^ Skerker JM, Prasol MS, Perchuk BS, Biondi EG, Laub MT (October 2005). "Two-component signal transduction pathways regulating growth and cell cycle progression in a bacterium: a system-level analysis". PLoS Biol. 3 (10): e334. doi:10.1371/journal.pbio.0030334. PMC 1233412. PMID 16176121.
2. ^ Stock AM, Robinson VL, Goudreau PN (2000). "Two-component signal transduction". Annu. Rev. Biochem. 69: 183–215. doi:10.1146/annurev.biochem.69.1.183. PMID 10966457.

## Further reading

• Kehry MR, Doak TG, Dahlquist FW (1984). "Stimulus-induced changes in methylesterase activity during chemotaxis in Escherichia coli". J. Biol. Chem. 259 (19): 11828–35. PMID 6384215.

This article incorporates text from the public domain Pfam and InterPro IPR000673

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.

# CheB methylesterase

No Pfam abstract.

## Literature references

1. West AH, Martinez-Hackert E, Stock AM; , J Mol Biol 1995;250:276-290.: Crystal structure of the catalytic domain of the chemotaxis receptor methylesterase, CheB. PUBMED:7608974 EPMC:7608974

## External database links

This tab holds annotation information from the InterPro database.

# InterPro entry IPR000673

Two-component signal transduction systems enable bacteria to sense, respond, and adapt to a wide range of environments, stressors, and growth conditions [PUBMED:16176121]. Some bacteria can contain up to as many as 200 two-component systems that need tight regulation to prevent unwanted cross-talk [PUBMED:18076326]. These pathways have been adapted to response to a wide variety of stimuli, including nutrients, cellular redox state, changes in osmolarity, quorum signals, antibiotics, and more [PUBMED:12372152]. Two-component systems are comprised of a sensor histidine kinase (HK) and its cognate response regulator (RR) [PUBMED:10966457]. The HK catalyses its own auto-phosphorylation followed by the transfer of the phosphoryl group to the receiver domain on RR; phosphorylation of the RR usually activates an attached output domain, which can then effect changes in cellular physiology, often by regulating gene expression. Some HK are bifunctional, catalysing both the phosphorylation and dephosphorylation of their cognate RR. The input stimuli can regulate either the kinase or phosphatase activity of the bifunctional HK.

A variant of the two-component system is the phospho-relay system. Here a hybrid HK auto-phosphorylates and then transfers the phosphoryl group to an internal receiver domain, rather than to a separate RR protein. The phosphoryl group is then shuttled to histidine phosphotransferase (HPT) and subsequently to a terminal RR, which can evoke the desired response [PUBMED:11934609, PUBMED:11489844].

This entry represents the signal transduction response regulator CheB involved in chemotaxis. CheB methylesterase is responsible for removing the methyl group from the gamma-glutamyl methyl ester residues in the methyl-accepting chemotaxis proteins (MCP). The enzyme catalyses the reaction: protein L-glutamate O-methyl ester and water is converted to protein L-glutamate and methanol. CheB is regulated through phosphorylation by CheA. The N-terminal region of the protein is similar to that of other regulatory components of sensory transduction systems. The Myxococcus xanthus FrzG protein also belongs to this family, and is required for the normal aggregation of cells during fruiting body formation.

### Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

# Domain organisation

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

Loading domain graphics...

# 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...

## View options

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
(180)
Full
(3655)
Representative proteomes NCBI
(3093)
Meta
(363)
RP15
(399)
RP35
(770)
RP55
(1013)
RP75
(1223)
Jalview View  View  View  View  View  View  View  View
HTML View  View  View  View  View  View
PP/heatmap 1 View  View  View  View  View
Pfam viewer View  View

1Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: available, not generated, not available.

## Format an alignment

Seed
(180)
Full
(3655)
Representative proteomes NCBI
(3093)
Meta
(363)
RP15
(399)
RP35
(770)
RP55
(1013)
RP75
(1223)
Alignment:
Format:
Order:
Sequence:
Gaps:
Download/view:

## Download options

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
(180)
Full
(3655)
Representative proteomes NCBI
(3093)
Meta
(363)
RP15
(399)
RP35
(770)
RP55
(1013)
RP75
(1223)
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.

# HMM logo

HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...

# 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: Sarah Teichmann Previous IDs: none Type: Domain Author: Finn RD, Bateman A Number in seed: 180 Number in full: 3655 Average length of the domain: 180.30 aa Average identity of full alignment: 37 % Average coverage of the sequence by the domain: 42.15 %

## 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 20.4 20.4
Trusted cut-off 20.6 20.6
Noise cut-off 19.9 18.7
Model length: 182
Family (HMM) version: 12
Download: download the raw HMM for this family

# Species distribution

### Sunburst controls

Show

This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

Loading sunburst data...

### Tree controls

Hide

The tree shows the occurrence of this domain across different species. More...

Loading...

Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.

# Interactions

There are 2 interactions for this family. More...

# 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 CheB_methylest domain has been found. There are 4 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.

Loading structure mapping...