Q94702 (PPO1_PHYPO) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Intron-encoded endonuclease I-PpoI Short name=I-Ppo EC=3.1.-.-
Organism	Physarum polycephalum (Slime mold)
Taxonomic identifier	5791 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Amoebozoa › Mycetozoa › Myxogastria › Myxogastromycetidae › Physariida › Physaraceae › Physarum

Protein attributes

Sequence length	163 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Mediates the homing of a group I intron in the ribosomal DNA. Makes a four-base staggered cut in its ribosomal DNA target sequence.
Cofactor	Zinc.
Subunit structure	Homodimer.
Sequence caution	The sequence AAB65764.1 differs from that shown. Reason: Erroneous initiation.

Ontologies

Keywords
Biological process	Intron homing
Ligand	Zinc
Molecular function	Endonuclease Hydrolase Nuclease
Technical term	3D-structure
Gene Ontology (GO)
Biological_process	intron homing Inferred from electronic annotation. Source: UniProtKB-KW nucleic acid phosphodiester bond hydrolysis Inferred from electronic annotation. Source: GOC
Molecular_function	endonuclease activity 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

Chain

1 – 163

163

Intron-encoded endonuclease I-PpoI

PRO_0000192788

Secondary structure

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163

Helix Strand Turn

Details...

Helix

5 – 19

15

Beta strand

24 – 32

9

Beta strand

35 – 43

9

Beta strand

46 – 48

3

Beta strand

54 – 58

5

Beta strand

61 – 68

8

Beta strand

71 – 76

6

Turn

77 – 79

3

Helix

80 – 82

3

Beta strand

83 – 85

3

Beta strand

87 – 89

3

Beta strand

92 – 98

7

Helix

108 – 110

3

Beta strand

111 – 115

5

Helix

116 – 121

6

Helix

122 – 124

3

Turn

128 – 131

4

Beta strand

157 – 160

4

Sequences

	Sequence		Length	Mass (Da)
	Q94702 [UniParc]. Last modified December 15, 1998. Version 3. Checksum: A193B6F06B0D8EEF	FASTA	163	17,789
	10 20 30 40 50 60 MALTNAQILA VIDSWEETVG QFPVITHHVP LGGGLQGTLH CYEIPLAAPY GVGFAKNGPT 70 80 90 100 110 120 RWQYKRTINQ VVHRWGSHTV PFLLEPDNIN GKTCTASHLC HNTRCHNPLH LCWESLDDNK 130 140 150 160 GRNWCPGPNG GCVHAVVCLR QGPLYGPGAT VAGPQQRGSH FVV

References

[1]	"Characterization of I-Ppo, an intron-encoded endonuclease that mediates homing of a group I intron in the ribosomal DNA of Physarum polycephalum." Muscarella D.E., Ellison E.L., Ruoff B.M., Vogt V.M. Mol. Cell. Biol. 10:3386-3396(1990) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	Vogt V.M. Submitted (AUG-1997) to the EMBL/GenBank/DDBJ databases Cited for: SEQUENCE REVISION.
[3]	"DNA binding and cleavage by the nuclear intron-encoded homing endonuclease I-PpoI." Flick K.E., Jurica M.S., Monnat R.J. Jr., Stoddard B.L. Nature 394:96-101(1998) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS).
[4]	"A novel endonuclease mechanism directly visualized for I-PpoI." Galburt E.A., Chevalier B., Tang W., Jurica M.S., Flick K.E., Monnat R.J. Jr., Stoddard B.L. Nat. Struct. Biol. 6:1096-1099(1999) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.93 ANGSTROMS).
[5]	"Conformational changes and cleavage by the homing endonuclease I-PpoI: a critical role for a leucine residue in the active site." Galburt E.A., Chadsey M.S., Jurica M.S., Chevalier B.S., Erho D., Tang W., Monnat R.J. Jr., Stoddard B.L. J. Mol. Biol. 300:877-887(2000) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS).
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

M38131 Genomic DNA. Translation: AAB65765.1.
M38131 Genomic DNA. Translation: AAB65764.1. Different initiation.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1A73	X-ray	1.80	A/B	1-163	[»]
1A74	X-ray	2.20	A/B	1-163	[»]
1CYQ	X-ray	1.93	A/B	2-163	[»]
1CZ0	X-ray	2.10	A/B	2-163	[»]
1EVW	X-ray	3.10	A/B/C/D	1-163	[»]
1EVX	X-ray	2.00	A/B	2-163	[»]
1IPP	X-ray	2.20	A/B	1-163	[»]
2O6M	X-ray	2.30	A/B	1-163	[»]

ProteinModelPortal

Q94702.

SMR

Q94702. Positions 2-163.

ModBase

Search...

Protein family/group databases

REBASE

2469. I-PpoI.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Family and domain databases

ProtoNet

Search...

Other

EvolutionaryTrace

Q94702.

Entry information

Entry name

PPO1_PHYPO

Accession

Primary (citable) accession number: Q94702

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 15, 1998
Last sequence update:	December 15, 1998
Last modified:	April 3, 2013
This is version 52 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)