5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase

Contribute

Send feedback

Read comments (0) or add your own

Reviewed, UniProtKB/Swiss-Prot P0AF12 (MTNN_ECOLI)

Last modified November 3, 2009. Version 44. History...

Clusters with 100%, 90%, 50% identity |

Documents (4) |

Third-party data |

Customize display

text xml rdf/xml gff fasta

Names and origin · Protein attributes · General annotation (Comments) · Ontologies · Sequence annotation (Features) · Sequences · References · Cross-references · Entry information · Relevant documents

Hide | Top

Names and origin

Protein names

Recommended name:
    5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase
      Short name=MTA/SAH nucleosidase
      Short name=MTAN
    EC=3.2.2.9
Alternative name(s):
    5'-methylthioadenosine nucleosidase
      Short name=MTA nucleosidase
    S-adenosylhomocysteine nucleosidase
      Short name=SAH nucleosidase
      Short name=AdoHcy nucleosidase
      Short name=SRH nucleosidase
    P46

Gene names

Name:	mtnN
Synonyms:	mtn, pfs, yadA
Ordered Locus Names:	b0159, JW0155

Organism

Escherichia coli (strain K12) [Complete proteome] [HAMAP]

Taxonomic identifier

83333 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Escherichia

Hide | Top

Protein attributes

Sequence length	232 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

Hide | Top

General annotation (Comments)

Function	Catalyzes the irreversible cleavage of the glycosidic bond in both 5'-methylthioadenosine (MTA) and S-adenosylhomocysteine (SAH/AdoHcy) to adenine and the corresponding thioribose, 5'-methylthioribose and S-ribosylhomocysteine, respectively. Can also use 5'-isobutylthioadenosine, 5'-n-butylthioadenosine, S-adenosyl-D-homocysteine, decarboxylated adenosylhomocysteine, deaminated adenosylhomocysteine and S-2-aza-adenosylhomocysteine as substrates. HAMAP MF_01684
Catalytic activity	S-adenosyl-L-homocysteine + H₂O = S-(5-deoxy-D-ribos-5-yl)-L-homocysteine + adenine. HAMAP MF_01684 S-methyl-5'-thioadenosine + H₂O = S-methyl-5-thio-D-ribose + adenine. HAMAP MF_01684
Enzyme regulation	Strongly inhibited by aryl-substituted MTA analogs, alkyl-substituted MTA analogs, 5'-methylthioformycin, 5'-chloroformycin, S-formycinylhomocysteine, 5'-methylthiotubercidin, S-tubercidinylhomocysteine and S-8-aza-adenosylhomocysteine. Poorly inhibited by 5'-isobutylthioinosine, 5'-n-butylthioinosine, 5'-methylthio-3-deaza-adenosine, 5'-isobutylthio-3-deaza-adenosine, S-n-6-methyl-3-deaza-adenosylhomocysteine, S-adenosylhomocysteine sulphoxide and Sinefungin. Ref.7 Ref.8 Ref.10 Ref.11
Pathway	Amino-acid biosynthesis; L-methionine biosynthesis via salvage pathway; S-methyl-5-thio-alpha-D-ribose 1-phosphate from S-methyl-5'-thioadenosine (hydrolase route): step 1/2. HAMAP MF_01684
Subunit structure	Homodimer. Ref.9
Sequence similarities	Belongs to the PNP/UDP phosphorylase family. MtnN subfamily.
Biophysicochemical properties	Kinetic parameters: K_M=0.43 µM for 5'-methylthioadenosine (at pH 7 and 37 degrees Celsius) HAMAP MF_01684 K_M=4.3 µM for S-adenosylhomocysteine (at pH 7 and 37 degrees Celsius) V_max=373 µmol/min/mg enzyme with 5'-methylthioadenosine as substrate (at pH 7 and 37 degrees Celsius) V_max=156 µmol/min/mg enzyme with S-adenosylhomocysteine as substrate (at pH 7 and 37 degrees Celsius) pH dependence: Exhibits activity across a broad pH range. Enzyme activity is moderately improved under acidic conditions. Temperature dependence: Optimum temperature is 37-45 degrees Celsius. Rapidly inactivated after exposure for 10 min at 55 degrees Celsius.

Hide | Top

Ontologies

Keywords
Biological process	Amino-acid biosynthesis Methionine biosynthesis
Molecular function	Hydrolase
Technical term	3D-structure Complete proteome
Gene Ontology (GO)
Biological process	methionine biosynthetic process from S-adenosylmethionine Inferred from electronic annotation. Source: HAMAP methionine salvage Inferred from electronic annotation. Source: InterPro nucleoside catabolic process Inferred from electronic annotation. Source: InterPro
Molecular function	adenosylhomocysteine nucleosidase activity Inferred from electronic annotation. Source: HAMAP methylthioadenosine nucleosidase activity Inferred from electronic annotation. Source: HAMAP
Complete GO annotation...

Hide | Top

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 232

232

5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase HAMAP MF_01684

PRO_0000164439

Regions

Region

173 – 174

Substrate binding HAMAP MF_01684

Sites

Active site

Proton acceptor Probable

Binding site

Substrate; via amide nitrogen HAMAP MF_01684

Binding site

152

Substrate; via amide nitrogen and carbonyl oxygen HAMAP MF_01684

Binding site

197

Substrate HAMAP MF_01684

Experimental info

Mutagenesis

E → Q: Loss of nucleosidase activity. Ref.12

Mutagenesis

197

D → N: Alters the hydrogen bond network in the active site. Ref.12

Sequence conflict

212 – 232

AVAAK…KLAHG → LLPLNSPA in AAA23678. Ref.1

Sequence conflict

212 – 232

AVAAK…KLAHG → LLPLNSPA in AAA24322. Ref.1

Secondary structure

232

Helix Strand Turn

Details...

Hide | Top

Sequences

Sequence

Length

Mass (Da)

Tools

P0AF12-1 [UniParc].

Last modified December 20, 2005. Version 1.
Checksum: 9B1FF9BEC39D4F2C
Show »

FASTA

232

24,354

        10         20         30         40         50         60 
MKIGIIGAME EEVTLLRDKI ENRQTISLGG CEIYTGQLNG TEVALLKSGI GKVAAALGAT 

        70         80         90        100        110        120 
LLLEHCKPDV IINTGSAGGL APTLKVGDIV VSDEARYHDA DVTAFGYEYG QLPGCPAGFK 

       130        140        150        160        170        180 
ADDKLIAAAE ACIAELNLNA VRGLIVSGDA FINGSVGLAK IRHNFPQAIA VEMEATAIAH 

       190        200        210        220        230 
VCHNFNVPFV VVRAISDVAD QQSHLSFDEF LAVAAKQSSL MVESLVQKLA HG

« Hide

Hide | Top

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Structure and regulation of the gene for dGTP triphosphohydrolase from Escherichia coli." Wurgler S.M., Richardson C.C. Proc. Natl. Acad. Sci. U.S.A. 87:2740-2744(1990) [PubMed: 2157212] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: K12.
[2]	"Cloning and expression of Escherichia coli 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase: identification of the pfs gene product." Cornell K.A., Riscoe M.K. Biochim. Biophys. Acta 1396:8-14(1998) [PubMed: 9524204] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], CHARACTERIZATION.
[3]	"Systematic sequencing of the Escherichia coli genome: analysis of the 2.4-4.1 min (110,917-193,643 bp) region." Fujita N., Mori H., Yura T., Ishihama A. Nucleic Acids Res. 22:1637-1639(1994) [PubMed: 8202364] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[4]	"Sequence of minutes 4-25 of Escherichia coli." Chung E., Allen E., Araujo R., Aparicio A.M., Davis K., Duncan M., Federspiel N., Hyman R., Kalman S., Komp C., Kurdi O., Lew H., Lin D., Namath A., Oefner P., Roberts D., Schramm S., Davis R.W. Submitted (JAN-1997) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[5]	"The complete genome sequence of Escherichia coli K-12." Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V., Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F., Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B., Shao Y. Science 277:1453-1474(1997) [PubMed: 9278503] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[6]	"Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 and W3110." Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S., Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T. Mol. Syst. Biol. 2:E1-E5(2006) [PubMed: 16738553] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[7]	"Escherichia coli S-adenosylhomocysteine/5'-methylthioadenosine nucleosidase. Purification, substrate specificity and mechanism of action." Della Ragione F., Porcelli M., Carteni-Farina M., Zappia V., Pegg A.E. Biochem. J. 232:335-341(1985) [PubMed: 3911944] [Abstract] Cited for: BIOPHYSICOCHEMICAL PROPERTIES, ENZYME REGULATION.
[8]	"Characterization of recombinant Eschericha coli 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase: analysis of enzymatic activity and substrate specificity." Cornell K.A., Swarts W.E., Barry R.D., Riscoe M.K. Biochem. Biophys. Res. Commun. 228:724-732(1996) [PubMed: 8941345] [Abstract] Cited for: BIOPHYSICOCHEMICAL PROPERTIES, ENZYME REGULATION.
[9]	"Structure of E. coli 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase reveals similarity to the purine nucleoside phosphorylases." Lee J.E., Cornell K.A., Riscoe M.K., Howell P.L. Structure 9:941-953(2001) [PubMed: 11591349] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS) IN COMPLEX WITH SUBSTRATE, SUBUNIT.
[10]	"Structure of Escherichia coli 5'-methylthioadenosine/ S-adenosylhomocysteine nucleosidase inhibitor complexes provide insight into the conformational changes required for substrate binding and catalysis." Lee J.E., Cornell K.A., Riscoe M.K., Howell P.L. J. Biol. Chem. 278:8761-8770(2003) [PubMed: 12496243] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS) IN COMPLEX WITH SUBSTRATE ANALOGS, ENZYME REGULATION.
[11]	"Femtomolar transition state analogue inhibitors of 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase from Escherichia coli." Singh V., Evans G.B., Lenz D.H., Mason J.M., Clinch K., Mee S., Painter G.F., Tyler P.C., Furneaux R.H., Lee J.E., Howell P.L., Schramm V.L. J. Biol. Chem. 280:18265-18273(2005) [PubMed: 15749708] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS) IN COMPLEX WITH SUBSTRATE ANALOGS, ENZYME REGULATION.
[12]	"Structural snapshots of MTA/AdoHcy nucleosidase along the reaction coordinate provide insights into enzyme and nucleoside flexibility during catalysis." Lee J.E., Smith G.D., Horvatin C., Huang D.J., Cornell K.A., Riscoe M.K., Howell P.L. J. Mol. Biol. 352:559-574(2005) [PubMed: 16109423] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.1 ANGSTROMS) IN COMPLEX WITH SUBSTRATE ANALOGS, MUTANTS GLN-197 AND GLN-12, REACTION MECHANISM, MUTAGENESIS OF GLU-12 AND ASP-197.
+	Additional computationally mapped references.

Hide | Top

Cross-references

Sequence databases

M31772 Genomic DNA. Translation: AAA23678.1. Different initiation.
U24438 Genomic DNA. Translation: AAC38291.1.
M83735 Genomic DNA. Translation: AAA24322.1.
U70214 Genomic DNA. Translation: AAB08589.1.
U00096 Genomic DNA. Translation: AAC73270.1.
AP009048 Genomic DNA. Translation: BAB96736.1.

PIR

S45227.

RefSeq

AP_000820.1.
NP_414701.1.

3D structure databases

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1JYS	X-ray	1.90	A/B	1-232	[»]
1NC1	X-ray	2.00	A/B	1-232	[»]
1NC3	X-ray	2.20	A/B	1-232	[»]
1Y6Q	X-ray	2.20	A/B	1-232	[»]
1Y6R	X-ray	2.20	A/B	1-232	[»]
1Z5N	X-ray	2.10	A/B	1-232	[»]
1Z5O	X-ray	2.00	A/B	1-232	[»]
1Z5P	X-ray	2.00	A	1-232	[»]

ModBase

Search...

Protein-protein interaction databases

STRING

P0AF12.

2-D gel databases

SWISS-2DPAGE

P0AF12.

ECO2DBASE

C025.4. 6TH EDITION.

Genome annotation databases

GeneID

948542.

GenomeReviews

Gene locus JW0155 in contig AP009048_GR.
Gene locus b0159 in contig U00096_GR.

KEGG

ecj:JW0155.
eco:b0159.

Organism-specific databases

EchoBASE

EB1082.

EcoGene

EG11090. pfs.

CMR

Search...

Phylogenomic databases

HOGENOM

P0AF12.

OMA

AQVCHQF.

Enzyme and pathway databases

BioCyc

EcoCyc:EG11090-MON.
MetaCyc:EG11090-MON.

Gene expression databases

Genevestigator

P0AF12.

Family and domain databases

HAMAP

MF_01684.
[Tree]

InterPro

IPR010049. MTA_SAH_Nsdase.
IPR000845. Nucleoside_phosphorylase.
IPR018017. Nucleoside_phosphorylase_1.
[Graphical view]

PANTHER

PTHR21234. PNP_UDP. 1 hit.

Pfam

PF01048. PNP_UDP_1. 1 hit.
[Graphical view]

TIGRFAMs

TIGR01704. MTA/SAH-Nsdase. 1 hit.

ProtoNet

Search...

Other Resources

DrugBank

DB00173. Adenine.

Hide | Top

Entry information

Entry name

MTNN_ECOLI

Accession

Primary (citable) accession number: P0AF12
Secondary accession number(s): P24247

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 20, 2005
Last sequence update:	December 20, 2005
Last modified:	November 3, 2009
This is version 44 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)

Hide | Top