E9AD19 · RBSK_LEIMA
- ProteinRibokinase
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids329 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
Catalyzes the phosphorylation of ribose at O-5 in a reaction requiring ATP and magnesium. The resulting D-ribose-5-phosphate can then be used either for sythesis of nucleotides, histidine, and tryptophan, or as a component of the pentose phosphate pathway. Specifically phosphorylates D-ribose. Fails to phosphorylate 4, 5 or 6 D-carbon sugars (erythrose, threose, xylulose, arabinose, fructose and glucose).
Catalytic activity
- ATP + D-ribose = ADP + D-ribose 5-phosphate + H+
Cofactor
Note: Requires a divalent cation, most likely magnesium in vivo, as an electrophilic catalyst to aid phosphoryl group transfer. It is the chelate of the metal and the nucleotide that is the actual substrate.
Activity regulation
Activated by a monovalent cation that binds near, but not in, the active site. The most likely occupant of the site in vivo is potassium. Ion binding induces a conformational change that may alter substrate affinity.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
0.2 mM | ATP | |||||
0.3 mM | ribose |
kcat is 10.2 sec-1 with ATP as substrate and 10.8 sec-1 with ribose as substrate.
Pathway
Carbohydrate metabolism; D-ribose degradation; D-ribose 5-phosphate from beta-D-ribopyranose: step 2/2.
Features
Showing features for binding site, active site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 25-27 | substrate | ||||
Sequence: FLD | ||||||
Binding site | 53-57 | substrate | ||||
Sequence: GKGAN | ||||||
Binding site | 160 | substrate | ||||
Sequence: E | ||||||
Binding site | 209 | ATP (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Binding site | 245-250 | ATP (UniProtKB | ChEBI) | ||||
Sequence: TLGAAG | ||||||
Binding site | 272 | K+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 274 | K+ (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 277-278 | ATP (UniProtKB | ChEBI) | ||||
Sequence: GD | ||||||
Active site | 278 | Proton acceptor | ||||
Sequence: D | ||||||
Binding site | 278 | substrate | ||||
Sequence: D | ||||||
Binding site | 302 | ATP (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Binding site | 308 | K+ (UniProtKB | ChEBI) | ||||
Sequence: S | ||||||
Binding site | 311 | K+ (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Binding site | 313 | K+ (UniProtKB | ChEBI) | ||||
Sequence: G | ||||||
Binding site | 317 | K+ (UniProtKB | ChEBI) | ||||
Sequence: S |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | glycosome | |
Cellular Component | nucleus | |
Molecular Function | ATP binding | |
Molecular Function | metal ion binding | |
Molecular Function | ribokinase activity | |
Biological Process | D-ribose catabolic process | |
Biological Process | D-ribose metabolic process |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameRibokinase
- EC number
- Short namesRK
Gene names
Organism names
- Organism
- Strain
- Taxonomic lineageEukaryota > Discoba > Euglenozoa > Kinetoplastea > Metakinetoplastina > Trypanosomatida > Trypanosomatidae > Leishmaniinae > Leishmania
Accessions
- Primary accessionE9AD19
Proteomes
Organism-specific databases
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000436026 | 1-329 | Ribokinase | |||
Sequence: MHRVQNVQSHVGEYAPDILVVGSCFLDYVGYVDHMPQVGETMHSESFHKGFGGKGANQAVAAGRLGAKVAMVSMVGTDGDGSDYIKELERNGVHTAYMLRTGKSSTGLAMILVDTKSSNNEIVICPNATNYFTPELLRAQTSNYEKILHTGLKYLICQNEIPLPTTLDTIKEAHSRGVYTVFNSAPAPKPAEVEQIKPFLPYVSLFCPNEVEAALITGMKVTDTESAFRAIKALQQLGVRDVVITLGAAGFALSENGAEPVHVTGKHVKAVDTTGAGDCFVGSMVYFMSRGRNLLEACKRANECAAISVTRKGTQLSYPHPSELPAGVT |
Interaction
Structure
Family & Domains
Sequence similarities
Belongs to the carbohydrate kinase PfkB family. Ribokinase subfamily.
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length329
- Mass (Da)35,342
- Last updated2011-04-05 v1
- ChecksumFAD47833EFCEFE8E
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
FR796423 EMBL· GenBank· DDBJ | CBZ12102.1 EMBL· GenBank· DDBJ | Genomic DNA |