Q2RXH9 · MTAP_RHORT
- ProteinS-methyl-5'-thioadenosine phosphorylase
- GenemtnP
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids294 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
Catalyzes the reversible phosphorylation of S-methyl-5'-thioadenosine (MTA) to adenine and 5-methylthioribose-1-phosphate (PubMed:23042035, PubMed:31950558).
Involved in the breakdown of MTA, a major by-product of polyamine biosynthesis. Responsible for the first step in the methionine salvage pathway after MTA has been generated from S-adenosylmethionine. Has broad substrate specificity with 6-aminopurine nucleosides as preferred substrates (By similarity).
Also catalyzes the phosphorylation of 5'-deoxyadenosine (5'dAdo) to 5-deoxyribose 1-phosphate (PubMed:31950558).
Part of a bifunctional DHAP-shunt salvage pathway for SAM by-products (PubMed:31950558).
Involved in the breakdown of MTA, a major by-product of polyamine biosynthesis. Responsible for the first step in the methionine salvage pathway after MTA has been generated from S-adenosylmethionine. Has broad substrate specificity with 6-aminopurine nucleosides as preferred substrates (By similarity).
Also catalyzes the phosphorylation of 5'-deoxyadenosine (5'dAdo) to 5-deoxyribose 1-phosphate (PubMed:31950558).
Part of a bifunctional DHAP-shunt salvage pathway for SAM by-products (PubMed:31950558).
Catalytic activity
- phosphate + S-methyl-5'-thioadenosine = adenine + S-methyl-5-thio-alpha-D-ribose 1-phosphateThis reaction proceeds in the forward direction.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
14 μM | 5'-methylthioadenosine | |||||
40 μM | 5'-deoxyadenosine | |||||
41 μM | adenine |
kcat is 4.5 sec-1 with 5'-methylthioadenosine as substrate. kcat is 6.7 sec-1 with 5'-deoxyadenosine as substrate (PubMed:23042035).
kcat is 0.06 sec-1 with adenine as substrate (PubMed:31950558).
kcat is 0.06 sec-1 with adenine as substrate (PubMed:31950558).
Pathway
Amino-acid biosynthesis; L-methionine biosynthesis via salvage pathway; S-methyl-5-thio-alpha-D-ribose 1-phosphate from S-methyl-5'-thioadenosine (phosphorylase route): step 1/1.
Features
Showing features for binding site, site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 16 | phosphate (UniProtKB | ChEBI) | ||||
Sequence: S | ||||||
Binding site | 58-59 | phosphate (UniProtKB | ChEBI) | ||||
Sequence: RH | ||||||
Binding site | 91-92 | phosphate (UniProtKB | ChEBI) | ||||
Sequence: SA | ||||||
Site | 171 | Important for substrate specificity | ||||
Sequence: S | ||||||
Binding site | 189 | substrate | ||||
Sequence: M | ||||||
Binding site | 190 | phosphate (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 213-215 | substrate | ||||
Sequence: DFD | ||||||
Site | 226 | Important for substrate specificity | ||||
Sequence: V |
GO annotations
Aspect | Term | |
---|---|---|
Molecular Function | S-methyl-5-thioadenosine phosphorylase activity | |
Biological Process | L-methionine salvage from methylthioadenosine | |
Biological Process | purine ribonucleoside salvage |
Keywords
- Molecular function
- Biological process
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameS-methyl-5'-thioadenosine phosphorylase
- EC number
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageBacteria > Pseudomonadota > Alphaproteobacteria > Rhodospirillales > Rhodospirillaceae > Rhodospirillum
Accessions
- Primary accessionQ2RXH9
Proteomes
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000415099 | 1-294 | S-methyl-5'-thioadenosine phosphorylase | |||
Sequence: MSEAYRQPVLGVIGGSGVYDIDGLEGARWQTVESPFGDVSDQILRGTLDGLEMAFLPRHGRGHVLAPSDVNYRANIDALKRAGVTEILSVSAVGSLAEDLPPGTFVIADQFIDRTFAREKSFFGKGLVAHVSMAHPVSAWLGDRVEEVLADLAIPHRRGGTYLCMEGPQFSTLAESNLYRQWGCHVIGMTNMPEAKLAREAEIAYCTVAMVTDFDCWHPDHDHVSVEAVVRVLLQNADKARSLVKAMPAKLKDRPYPLPDGSHRSLDNAIITHPDRRNPGMARKLSAVAGRVLG |
Interaction
Structure
Sequence
- Sequence statusComplete
- Length294
- Mass (Da)32,078
- Last updated2006-01-24 v1
- Checksum58481196C7CCFB4B
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
CP000230 EMBL· GenBank· DDBJ | ABC21166.1 EMBL· GenBank· DDBJ | Genomic DNA |