ID A0A1K1U5G7_9GAMM Unreviewed; 244 AA.
AC A0A1K1U5G7;
DT 15-FEB-2017, integrated into UniProtKB/TrEMBL.
DT 15-FEB-2017, sequence version 1.
DT 24-JAN-2024, entry version 26.
DE RecName: Full=Probable S-methyl-5'-thioinosine phosphorylase {ECO:0000256|HAMAP-Rule:MF_01963};
DE EC=2.4.2.44 {ECO:0000256|HAMAP-Rule:MF_01963};
DE AltName: Full=5'-methylthioinosine phosphorylase {ECO:0000256|HAMAP-Rule:MF_01963};
DE Short=MTI phosphorylase {ECO:0000256|HAMAP-Rule:MF_01963};
DE Short=MTIP {ECO:0000256|HAMAP-Rule:MF_01963};
GN ORFNames=SAMN02745752_00460 {ECO:0000313|EMBL:SFX08026.1};
OS Marinospirillum alkaliphilum DSM 21637.
OC Bacteria; Pseudomonadota; Gammaproteobacteria; Oceanospirillales;
OC Oceanospirillaceae; Marinospirillum.
OX NCBI_TaxID=1122209 {ECO:0000313|EMBL:SFX08026.1, ECO:0000313|Proteomes:UP000182350};
RN [1] {ECO:0000313|EMBL:SFX08026.1, ECO:0000313|Proteomes:UP000182350}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=DSM 21637 {ECO:0000313|EMBL:SFX08026.1,
RC ECO:0000313|Proteomes:UP000182350};
RA Jaros S., Januszkiewicz K., Wedrychowicz H.;
RL Submitted (NOV-2016) to the EMBL/GenBank/DDBJ databases.
CC -!- FUNCTION: Catalyzes the reversible phosphorylation of S-methyl-5'-
CC thioinosine (MTI) to hypoxanthine and 5-methylthioribose-1-phosphate.
CC Involved in the breakdown of S-methyl-5'-thioadenosine (MTA), a major
CC by-product of polyamine biosynthesis. Catabolism of (MTA) occurs via
CC deamination to MTI and phosphorolysis to hypoxanthine.
CC {ECO:0000256|HAMAP-Rule:MF_01963}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=phosphate + S-methyl-5'-thioinosine = hypoxanthine + S-methyl-
CC 5-thio-alpha-D-ribose 1-phosphate; Xref=Rhea:RHEA:30643,
CC ChEBI:CHEBI:17368, ChEBI:CHEBI:43474, ChEBI:CHEBI:48595,
CC ChEBI:CHEBI:58533; EC=2.4.2.44; Evidence={ECO:0000256|HAMAP-
CC Rule:MF_01963};
CC -!- PATHWAY: Purine metabolism; purine nucleoside salvage.
CC {ECO:0000256|HAMAP-Rule:MF_01963}.
CC -!- SUBUNIT: Homotrimer. {ECO:0000256|HAMAP-Rule:MF_01963}.
CC -!- MISCELLANEOUS: Although this enzyme belongs to the family of MTA
CC phosphorylases based on sequence homology, it has been shown that
CC conserved amino acid substitutions in the substrate binding pocket
CC convert the substrate specificity of this enzyme from 6-aminopurines to
CC 6-oxopurines. {ECO:0000256|HAMAP-Rule:MF_01963}.
CC -!- SIMILARITY: Belongs to the PNP/MTAP phosphorylase family. MTAP
CC subfamily. {ECO:0000256|HAMAP-Rule:MF_01963}.
CC -!- CAUTION: Lacks conserved residue(s) required for the propagation of
CC feature annotation. {ECO:0000256|HAMAP-Rule:MF_01963}.
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DR EMBL; FPJW01000001; SFX08026.1; -; Genomic_DNA.
DR RefSeq; WP_072324678.1; NZ_FPJW01000001.1.
DR AlphaFoldDB; A0A1K1U5G7; -.
DR STRING; 1122209.SAMN02745752_00460; -.
DR OrthoDB; 1523230at2; -.
DR UniPathway; UPA00606; -.
DR Proteomes; UP000182350; Unassembled WGS sequence.
DR GO; GO:0017061; F:S-methyl-5-thioadenosine phosphorylase activity; IEA:InterPro.
DR GO; GO:0006166; P:purine ribonucleoside salvage; IEA:UniProtKB-UniRule.
DR CDD; cd09010; MTAP_SsMTAPII_like_MTIP; 1.
DR Gene3D; 3.40.50.1580; Nucleoside phosphorylase domain; 1.
DR HAMAP; MF_01963; MTAP; 1.
DR InterPro; IPR010044; MTAP.
DR InterPro; IPR000845; Nucleoside_phosphorylase_d.
DR InterPro; IPR035994; Nucleoside_phosphorylase_sf.
DR InterPro; IPR018099; Purine_phosphorylase-2_CS.
DR PANTHER; PTHR42679; S-METHYL-5'-THIOADENOSINE PHOSPHORYLASE; 1.
DR PANTHER; PTHR42679:SF2; S-METHYL-5'-THIOADENOSINE PHOSPHORYLASE; 1.
DR Pfam; PF01048; PNP_UDP_1; 1.
DR SUPFAM; SSF53167; Purine and uridine phosphorylases; 1.
DR PROSITE; PS01240; PNP_MTAP_2; 1.
PE 3: Inferred from homology;
KW Glycosyltransferase {ECO:0000256|HAMAP-Rule:MF_01963};
KW Purine salvage {ECO:0000256|HAMAP-Rule:MF_01963};
KW Reference proteome {ECO:0000313|Proteomes:UP000182350};
KW Transferase {ECO:0000256|HAMAP-Rule:MF_01963}.
FT DOMAIN 2..242
FT /note="Nucleoside phosphorylase"
FT /evidence="ECO:0000259|Pfam:PF01048"
FT BINDING 8
FT /ligand="phosphate"
FT /ligand_id="ChEBI:CHEBI:43474"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01963"
FT BINDING 50..51
FT /ligand="phosphate"
FT /ligand_id="ChEBI:CHEBI:43474"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01963"
FT BINDING 183
FT /ligand="substrate"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01963"
FT BINDING 184
FT /ligand="phosphate"
FT /ligand_id="ChEBI:CHEBI:43474"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01963"
FT BINDING 207..209
FT /ligand="substrate"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01963"
FT SITE 165
FT /note="Important for substrate specificity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01963"
FT SITE 219
FT /note="Important for substrate specificity"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_01963"
SQ SEQUENCE 244 AA; 26083 MW; 6795BDFBBC2285D3 CRC64;
MLAIIGGTGL TQIEGVQLLA ERSAHTALGS ASSPVTEARL EGQPVLFLAR HGHPHRIPPH
RINYRANLLA LQAAGATRIL AINAVGGIDP AFTPGSLVLP DQIIDYTWGR EATFFDGDYL
PLKHLDFTWP YDKNLRKSLL AVAAKEKIPV HAGGVYGATQ GPRLETAAEI TRMARDGCTL
VGMTGMPEAM LARELELPYA CLSLVVNPAA GLSSEAITMA GIEQVLQQGM GEVLKLLRAF
VRTS
//
