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HAMAP rule MF_00850

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General rule information [?]

Accession MF_00850
Dates 23-MAR-2020 (Created)
19-NOV-2022 (Last updated, Version 5)
Name POX
Scope
Bacteria
Template P07003 (POXB_ECOLI)

Propagated annotation [?]


Identifier, protein and gene names [?]

Identifier
POXB
Protein name
RecName: Full=Pyruvate dehydrogenase [ubiquinone];
EC 1.2.5.1;
AltName: Full=Pyruvate oxidase;
Short=POX;
AltName: Full=Pyruvate:ubiquinone-8 oxidoreductase;
Gene name
poxB

Comments [?]

Function A peripheral cell membrane enzyme that catalyzes the oxidative decarboxylation of pyruvate to form acetate and CO(2). It channels electrons from the cytoplasm to the respiratory chain at the cell membrane via ubiquinone.
Catalytic activity RHEA:27405: a ubiquinone + H2O + pyruvate = a ubiquinol + acetate + CO2
EC 1.2.5.1
Cofactor FAD
Note: Binds 1 FAD per subunit.
Mg(2+)
Note: Binds 1 Mg(2+) ion per subunit.
thiamine diphosphate
Note: Binds 1 thiamine pyrophosphate per subunit.
Activity regulation The C-terminus inhibits activity; it has to move for the enzyme to be active. Activated by lipid-binding, which occurs via the C-terminus.
Subunit Homotetramer.
case not defined <Property:Membrane> or <Property:Membrane=1>
Subcellular location Cell membrane; Peripheral membrane protein; Cytoplasmic side.
else case <Property:Membrane=2>
Subcellular location Cell inner membrane; Peripheral membrane protein; Cytoplasmic side.
end case
Domain Has 4 domains; the Pyr domain which binds the pyrimidine moiety of the thiamine pyrophosphate cofactor, the FAD-binding domain, the PP-binding domain which binds the pyrophosphate portion of thiamine pyrophosphate and the C-terminal membrane binding region. The C-terminus is held closely against the rest of the protein and covers the active site; during activation it unfolds from the rest of the protein and forms an amphipathic helix upon membrane binding, exposing the active site.
Similarity Belongs to the TPP enzyme family.

Keywords [?]

case defined <Property:Membrane> and <Property:Membrane=2>
end case

Gene Ontology [?]

GO:0005886; Cellular component: plasma membrane.
GO:0050660; Molecular function: flavin adenine dinucleotide binding.
GO:0008289; Molecular function: lipid binding.
GO:0000287; Molecular function: magnesium ion binding.
GO:0052737; Molecular function: pyruvate dehydrogenase (quinone) activity.
GO:0030976; Molecular function: thiamine pyrophosphate binding.
GO:0042867; Biological process: pyruvate catabolic process.
GO:0048039; Molecular function: ubiquinone binding.

Cross-references [?]

PROSITE PS00187; TPP_ENZYMES; 1;
Pfam PF02775; TPP_enzyme_C; 1;
PF00205; TPP_enzyme_M; 1;
PF02776; TPP_enzyme_N; 1;

Computed features [?]

General Coiled_coil; -; 0-unlimited; trigger=yes;

Features [?]

From: POXB_ECOLI (P07003)
Key     From     To       Description   Tag   Condition   FTGroup
BINDING     251     254       /ligand="FAD" /ligand_id="ChEBI:CHEBI:57692     T-G-L-[IL]  
BINDING     274     278       /ligand="FAD" /ligand_id="ChEBI:CHEBI:57692     [TS]-x-[FL]-P-[YF]  
REGION     1     182       Pyr domain        
REGION     183     334       FAD-binding domain        
REGION     335     530       PP-binding domain        
BINDING     406     408       /ligand="thiamine diphosphate" /ligand_id="ChEBI:CHEBI:58937     [GA]-[ST]-M  
BINDING     433     435       /ligand="thiamine diphosphate" /ligand_id="ChEBI:CHEBI:58937     D-G-G  
BINDING     460     466       /ligand="thiamine diphosphate" /ligand_id="ChEBI:CHEBI:58937        
REGION     531     572       Membrane-binding domain        
BINDING     433     433       /ligand="Mg(2+)" /ligand_id="ChEBI:CHEBI:18420     D  
BINDING     460     460       /ligand="Mg(2+)" /ligand_id="ChEBI:CHEBI:18420     N  
BINDING     50     50       /ligand="thiamine diphosphate" /ligand_id="ChEBI:CHEBI:58937     E  
BINDING     292     292       /ligand="FAD" /ligand_id="ChEBI:CHEBI:57692     D  
SITE     465     465       Moves into active site upon enzyme activation, plays a role in electron transfer     F  

Additional information [?]

Size range 528-616 amino acids
Related rules None
Fusion None