Q27546 (IUNH_CRIFA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Inosine-uridine preferring nucleoside hydrolase
Short name=IU-NH
Short name=IU-nucleoside hydrolase
EC=3.2.2.-

Alternative name(s):
Non-specific nucleoside hydrolase
Purine nucleosidase

Gene names

Name:

IUNH

Organism

Crithidia fasciculata

Taxonomic identifier

5656 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Euglenozoa › Kinetoplastida › Trypanosomatidae › Leishmaniinae › Crithidia

Protein attributes

Sequence length	315 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Catalyzes the hydrolysis of all of the commonly occurring purine and pyrimidine nucleosides into ribose and the associated base, but has a preference for inosine and uridine as substrates.
Catalytic activity	A purine nucleoside + H2O = D-ribose + a purine base.
Cofactor	Calcium.
Pathway	Purine metabolism; purine nucleoside salvage.
Subunit structure	Homotetramer.
Sequence similarities	Belongs to the IUNH family.
Mass spectrometry	Molecular mass is 34194±4 Da from positions 2 - 315. Determined by ESI. Ref.1

Ontologies

Keywords
Biological process	Nucleotide metabolism
Ligand	Calcium Metal-binding
Molecular function	Glycosidase Hydrolase
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Biological_process	nucleotide metabolic process Inferred from electronic annotation. Source: UniProtKB-KW
Molecular_function	hydrolase activity, hydrolyzing N-glycosyl compounds Inferred from electronic annotation. Source: InterPro metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Initiator methionine

1

1

Removed

Chain

2 – 315

314

Inosine-uridine preferring nucleoside hydrolase

PRO_0000206810

Sites

Active site

241

1

Metal binding

10

1

Calcium

Metal binding

15

1

Calcium

Metal binding

126

1

Calcium

Metal binding

242

1

Calcium

Binding site

14

1

Substrate

Binding site

160

1

Substrate

Binding site

166

1

Substrate

Binding site

168

1

Substrate

Experimental info

Mutagenesis

241

1

H → A: Loss of activity.

Secondary structure

1

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315

Helix Strand Turn

Details...

Beta strand

3 – 9

7

Helix

13 – 24

12

Beta strand

28 – 35

8

Beta strand

37 – 40

4

Helix

42 – 55

14

Beta strand

63 – 65

3

Beta strand

71 – 73

3

Helix

79 – 82

4

Beta strand

84 – 87

4

Helix

105 – 115

11

Beta strand

121 – 125

5

Helix

130 – 138

9

Helix

142 – 145

4

Beta strand

148 – 152

5

Beta strand

160 – 164

5

Helix

167 – 170

4

Helix

173 – 181

9

Beta strand

182 – 184

3

Beta strand

186 – 189

4

Helix

191 – 194

4

Helix

201 – 208

8

Helix

213 – 230

18

Beta strand

236 – 239

4

Helix

242 – 250

9

Helix

252 – 254

3

Beta strand

255 – 259

5

Beta strand

262 – 264

3

Turn

269 – 273

5

Beta strand

275 – 277

3

Beta strand

288 – 295

8

Helix

297 – 311

15

Sequences

	Sequence		Length	Mass (Da)
	Q27546 [UniParc]. Last modified January 23, 2007. Version 3. Checksum: B88CF9DA41B53F43	FASTA	315	34,326
	10 20 30 40 50 60 MPKKIILDCD PGLDDAVAIL LAHGNPEIEL LAITTVVGNQ TLAKVTRNAQ LVADIAGITG 70 80 90 100 110 120 VPIAAGCDKP LVRKIMTAGH IHGESGMGTV AYPAEFKNKV DERHAVNLII DLVMSHEPKT 130 140 150 160 170 180 ITLVPTGGLT NIAMAARLEP RIVDRVKEVV LMGGGYHEGN ATSVAEFNII IDPEAAHIVF 190 200 210 220 230 240 NESWQVTMVG LDLTHQALAT PPILQRVKEV DTNPARFMLE IMDYYTKIYQ SNRYMAAAAV 250 260 270 280 290 300 HDPCAVAYVI DPSVMTTERV PVDIELTGKL TLGMTVADFR NPRPEHCHTQ VAVKLDFEKF 310 WGLVLDALER IGDPQ

References

[1]	"Inosine-uridine nucleoside hydrolase from Crithidia fasciculata. Genetic characterization, crystallization, and identification of histidine 241 as a catalytic site residue." Gopaul D.N., Meyer S.L., Degano M., Sacchettini J.C., Schramm V.L. Biochemistry 35:5963-5970(1996) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PARTIAL PROTEIN SEQUENCE, MASS SPECTROMETRY, MUTAGENESIS.
[2]	"Three-dimensional structure of the inosine-uridine nucleoside N-ribohydrolase from Crithidia fasciculata." Degano M., Gopaul D.N., Scapin G., Schramm V.L., Sacchettini J.C. Biochemistry 35:5971-5981(1996) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS) IN COMPLEX WITH SUBSTRATE AND CALCIUM IONS.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

U43371 Genomic DNA. Translation: AAC47119.1.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1MAS	X-ray	2.50	A/B	3-315	[»]
2MAS	X-ray	2.30	A/B/C/D	3-314	[»]

ProteinModelPortal

Q27546.

SMR

Q27546. Positions 3-314.

ModBase

Search...

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Enzyme and pathway databases

UniPathway

UPA00606.

Family and domain databases

Gene3D

3.90.245.10. 1 hit.

InterPro

IPR015910. I/U_nuclsd_hydro_CS.
IPR023186. Inosine/uridine_hydrolase.
IPR001910. Inosine/uridine_hydrolase_dom.
[Graphical view]

PANTHER

PTHR12304. PTHR12304. 1 hit.

Pfam

PF01156. IU_nuc_hydro. 1 hit.
[Graphical view]

SUPFAM

SSF53590. I/U_nuclsd_hydro. 1 hit.

PROSITE

PS01247. IUNH. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

EvolutionaryTrace

Q27546.

Entry information

Entry name

IUNH_CRIFA

Accession

Primary (citable) accession number: Q27546

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 1, 1997
Last sequence update:	January 23, 2007
Last modified:	April 3, 2013
This is version 75 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)