P10378 · ENTE_ECOLI
- ProteinEnterobactin synthase component E
- GeneentE
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids536 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Involved in the biosynthesis of the siderophore enterobactin (enterochelin), which is a macrocyclic trimeric lactone of N-(2,3-dihydroxybenzoyl)-serine. The serine trilactone serves as a scaffolding for the three catechol functionalities that provide hexadentate coordination for the tightly ligated iron2+ atoms. EntE proccesses via a two-step adenylation-ligation reaction (bi-uni-uni-bi ping-pong mechanism). First, it catalyzes the activation of the carboxylate group of 2,3-dihydroxy-benzoate (DHB), via a reversible ATP-dependent pyrophosphate exchange reactions to yield the acyladenylate intermediate 2,3-dihydroxybenzoyl-AMP. It can also transfer AMP to salicylate, 2,4-dihydroxybenzoate, gentisate and 2,3,4-trihydroxybenzoate. In the second step, DHB is transferred from 2,3-dihydroxybenzoyl-AMP onto the phosphopantetheinylated EntB (holo-EntB) to form DHB-holo-EntB. Then this product will serve in the formation of the amide bond between 2,3-dihydroxybenzoate (DHB) and L-serine. It can also transfer adenylated salicylate to holo-EntB.
Miscellaneous
In the absence of holo-EntB, EntE can transfer the adenylate moiety of the 2,3-dihydroxybenzoyl-AMP intermediate to ATP, generating the stress signaling molecule Ap4A involved in the regulation of cell division during oxidative stress, and releasing 2,3-dihydroxybenzoate. It seems that the expression of EntE during iron starvation produces Ap4A to slow growth until intracellular iron stores can be restored.
Catalytic activity
- 3 2,3-dihydroxybenzoate + 6 ATP + 3 L-serine = 6 AMP + 6 diphosphate + enterobactin + 4 H+
- 2,3-dihydroxybenzoyl-5'-AMP + holo-[ACP] = 2,3-dihydroxybenzoyl-[ACP] + AMP + H+
Activity regulation
Inhibited by the adenylate analogs, 5'-O-[N-(salicyl)sulfamoyl]adenosine (Sal-AMS) and 5'-O-[N-(2,3-dihydroxybenzoyl)sulfamoyl]adenosine (DHB-AMS). Adenylation of 2,3-dihydroxybenzoate (DHB) is enhanced by a protein-protein interaction between the EntA and EntE.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
0.4 μM | holo-EntB | 8.8 | 37 | |||
0.5 μM | holo-EntB | |||||
2.5 μM | DHB | 7.8 | 25 | |||
2.7 μM | DHB | |||||
2.9 μM | DHB | |||||
2.9 μM | holo-EntB | 7.8 | 25 | |||
23.3 μM | holo-EntB | 7.5 | 37 | |||
70 μM | 3-hydroxybenzoate | 7.8 | 25 | |||
70 μM | salicylate | 7.8 | 25 | |||
400 μM | 5,5-diadenosine tetraphosphate | |||||
430 μM | ATP | 7.8 | 25 | |||
1200 μM | ATP | |||||
3100 μM | 4-aminosalicylate | 7.8 | 25 | |||
34.2 mM | D-pantetheine | 7.8 | 25 |
Vmax | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|
3168.2 pmol/min/mg |
kcat is 0.3 sec-1 for 2,3-dihydroxybenzoate-AMP ligase activity with 3-hydroxybenzoate as substrate (at pH 7.8 and 25 degrees Celsius). kcat is 0.8 sec-1 for 2,3-dihydroxybenzoate-AMP ligase activity with salicylate as substrate (at pH 7.8 and 25 degrees Celsius). kcat is 0.9 sec-1 for S-dihydroxybenzoyltransferase activity with D-pantetheine as substrate (at pH 7.8 and 25 degrees Celsius). kcat is 2.8 sec-1 for 2,3-dihydroxybenzoate-AMP ligase activity with ATP and DHB as substrates (at pH 7.8 and 25 degrees Celsius). kcat is 2.8 sec-1 for S-dihydroxybenzoyltransferase activity with holo-EntB as substrate (at pH 7.8 and 25 degrees Celsius). kcat is 4.4 sec-1 for 2,3-dihydroxybenzoate-AMP ligase activity with 4-aminosalicylate as substrate (at pH 7.8 and 25 degrees Celsius). kcat is 5.94 sec-1 for S-dihydroxybenzoyltransferase activity with holo-EntB as substrate (at pH 7.8 and 25 degrees Celsius). kcat is 100 min-1 for S-dihydroxybenzoyltransferase activity with holo-EntB as substrate (at pH 8.8 and 37 degrees Celsius). kcat is 140 min-1 for S-dihydroxybenzoyltransferase activity with holo-EntB as substrate.
Pathway
Siderophore biosynthesis; enterobactin biosynthesis.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 235 | substrate | ||||
Sequence: N | ||||||
Binding site | 240 | substrate | ||||
Sequence: S | ||||||
Binding site | 309 | substrate | ||||
Sequence: G | ||||||
Binding site | 331 | substrate | ||||
Sequence: V | ||||||
Binding site | 335 | substrate | ||||
Sequence: A | ||||||
Binding site | 415 | substrate | ||||
Sequence: D | ||||||
Binding site | 432 | substrate | ||||
Sequence: K | ||||||
Binding site | 441 | substrate | ||||
Sequence: K |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytosol | |
Cellular Component | membrane | |
Molecular Function | 2,3-dihydroxybenzoate--[aryl-carrier protein] ligase | |
Molecular Function | 2,3-dihydroxybenzoate-serine ligase activity | |
Molecular Function | acyltransferase activity | |
Molecular Function | ATP binding | |
Biological Process | enterobactin biosynthetic process |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameEnterobactin synthase component E
- EC number
- Alternative names
Gene names
Organism names
- Organism
- Strains
- Taxonomic lineageBacteria > Pseudomonadota > Gammaproteobacteria > Enterobacterales > Enterobacteriaceae > Escherichia
Accessions
- Primary accessionP10378
- Secondary accessions
Proteomes
Subcellular Location
Phenotypes & Variants
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 437 | Catalyzes the adenylation reaction with 10% reduction of activity compared to the wild-type. 3% reduction of activity compared to the wild-type; when associated with D-473. | ||||
Sequence: R → D | ||||||
Mutagenesis | 473 | Catalyzes the adenylation reaction with same activity as the wild-type. 3% reduction of activity compared to the wild-type; when associated with D-437. | ||||
Sequence: K → D | ||||||
Mutagenesis | 494 | Catalyzes the adenylation reaction with same activity as the wild-type. | ||||
Sequence: R → D |
Chemistry
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000193075 | 1-536 | Enterobactin synthase component E | |||
Sequence: MSIPFTRWPEEFARRYREKGYWQDLPLTDILTRHAASDSIAVIDGERQLSYRELNQAADNLACSLRRQGIKPGETALVQLGNVAELYITFFALLKLGVAPVLALFSHQRSELNAYASQIEPALLIADRQHALFSGDDFLNTFVTEHSSIRVVQLLNDSGEHNLQDAINHPAEDFTATPSPADEVAYFQLSGGTTGTPKLIPRTHNDYYYSVRRSVEICQFTQQTRYLCAIPAAHNYAMSSPGSLGVFLAGGTVVLAADPSATLCFPLIEKHQVNVTALVPPAVSLWLQALIEGESRAQLASLKLLQVGGARLSATLAARIPAEIGCQLQQVFGMAEGLVNYTRLDDSAEKIIHTQGYPMCPDDEVWVADAEGNPLPQGEVGRLMTRGPYTFRGYYKSPQHNASAFDANGFYCSGDLISIDPEGYITVQGREKDQINRGGEKIAAEEIENLLLRHPAVIYAALVSMEDELMGEKSCAYLVVKEPLRAVQVRRFLREQGIAEFKLPDRVECVDSLPLTAVGKVDKKQLRQWLASRASA |
Proteomic databases
Expression
Induction
Under conditions of iron deficiency and by the fur protein.
Interaction
Subunit
Proteins EntB, EntD, EntE, and EntF form a multienzyme complex called enterobactin synthase. Monomer. EntA and EntE interact together.
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | Intact | |
---|---|---|---|---|---|
BINARY | P10378 | entA P15047 | 5 | EBI-550322, EBI-1118936 | |
BINARY | P10378 | entB P0ADI4 | 3 | EBI-550322, EBI-547993 |
Protein-protein interaction databases
Chemistry
Structure
Family & Domains
Features
Showing features for region.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 438-439 | Phosphopantetheine binding | ||||
Sequence: GG |
Sequence similarities
Belongs to the ATP-dependent AMP-binding enzyme family. EntE subfamily.
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length536
- Mass (Da)59,112
- Last updated1997-11-01 v3
- ChecksumF818942DFDD8DC99
Features
Showing features for sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Sequence conflict | 369-378 | in Ref. 1; CAA33158 | ||||
Sequence: DAEGNPLPQG → ECRRKSTAAR |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
X15058 EMBL· GenBank· DDBJ | CAA33158.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
U82598 EMBL· GenBank· DDBJ | AAB40794.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
U00096 EMBL· GenBank· DDBJ | AAC73695.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
AP009048 EMBL· GenBank· DDBJ | BAE76349.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
M24148 EMBL· GenBank· DDBJ | AAA16101.1 EMBL· GenBank· DDBJ | Unassigned DNA | ||
M36700 EMBL· GenBank· DDBJ | AAA18492.1 EMBL· GenBank· DDBJ | Genomic DNA |