Flavokinase Riboflavin kinase
SMART ACC:	SM000904
Description:	Riboflavin is converted into catalytically active cofactors (FAD and FMN) by the actions of riboflavin kinase, which converts it into FMN, and FAD synthetase, which adenylates FMN to FAD. Eukaryotes usually have two separate enzymes, while most prokaryotes have a single bifunctional protein that can carry out both catalyses, although exceptions occur in both cases. While eukaryotic monofunctional riboflavin kinase is orthologous to the bifunctional prokaryotic enzyme (PUBMED:14580199), the monofunctional FAD synthetase differs from its prokaryotic counterpart, and is instead related to the PAPS-reductase family (PUBMED:17049878). The bacterial FAD synthetase that is part of the bifunctional enzyme has remote similarity to nucleotidyl transferases and, hence, it may be involved in the adenylylation reaction of FAD synthetases (PUBMED:12517446). This entry represents riboflavin kinase, which occurs as part of a bifunctional enzyme or a stand-alone enzyme.
InterPro ACC:	IPR015865
InterPro abstract:	Riboflavin is converted into catalytically active cofactors (FAD and FMN) by the actions of riboflavin kinase ( EC:2.7.1.26 ), which converts it into FMN, and FAD synthetase ( EC:2.7.7.2 ), which adenylates FMN to FAD. Eukaryotes usually have two separate enzymes … expand Riboflavin is converted into catalytically active cofactors (FAD and FMN) by the actions of riboflavin kinase ( EC:2.7.1.26 ), which converts it into FMN, and FAD synthetase ( EC:2.7.7.2 ), which adenylates FMN to FAD. Eukaryotes usually have two separate enzymes, while most prokaryotes have a single bifunctional protein that can carry out both catalyses, although exceptions occur in both cases. While eukaryotic monofunctional riboflavin kinase is orthologous to the bifunctional prokaryotic enzyme [ PUBMED:14580199 ], the monofunctional FAD synthetase differs from its prokaryotic counterpart, and is instead related to the PAPS-reductase family [ PUBMED:17049878 ]. The bacterial FAD synthetase that is part of the bifunctional enzyme has remote similarity to nucleotidyl transferases and, hence, it may be involved in the adenylylation reaction of FAD synthetases [ PUBMED:12517446 ]. This entry represents the riboflavin kinase domains from bacteria and eukaryotes. collapse
GO process:	riboflavin biosynthetic process (GO:0009231)
GO function:	riboflavin kinase activity (GO:0008531)
Family alignment:	View the Family alignment or the Alignment consensus sequence
There are 21 800 Flavokinase domains in 21 799 proteins in SMART's NRDB database.

Taxonomic distribution of proteins containing Flavokinase domains

The tree below includes only several representative species and genera. The complete taxonomic breakdown of all proteins containing Flavokinase domains can be accessed here. Click the counts or percentage values to display the corresponding proteins.

Predicted cellular role

Cellular role:	Metabolic

Relevant references for this domain

Primary literature for the Flavokinase domain is listed below. Automatically-derived, secondary literature is also available.

KEGG pathways involving proteins which contain this domain

This information is based on the mapping of SMART genomic protein database to KEGG orthologous groups. Percentages are related to the number of proteins containing a Flavokinase domain which could be assigned to a KEGG orthologous group, and not all proteins containing Flavokinase domains. Please note that proteins can be included in multiple pathways, ie. the numbers below will not add to 100%.

KEGG pathways

Some of these pathways are included in the interactive Pathways Explorer overview maps. Select an overview map and click the button below to highlight them in iPath.

KEGG orthologous groups

Some of these KOs are included in the interactive Pathways Explorer overview maps. Select an overview map and click the button below to highlight them in iPath.

3D structures in PDB containing this domain

Links to other resources describing this domain

InterPro	IPR015865
Pfam	Flavokinase