Annotations: 1CZ0

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
C [auth A]	d1cz0a_	Alpha and beta proteins (a+b)	His-Me finger endonucleases	His-Me finger endonucleases	Intron-encoded homing endonucleases	Intron-encoded homing endonuclease I-PpoI	(Badhamia polycephala ) [TaxId: 5791 ],	SCOPe (2.08)
D [auth B]	d1cz0b_	Alpha and beta proteins (a+b)	His-Me finger endonucleases	His-Me finger endonucleases	Intron-encoded homing endonucleases	Intron-encoded homing endonuclease I-PpoI	(Badhamia polycephala ) [TaxId: 5791 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
C [auth A]	SCOP2B Superfamily	His-Me finger endonucleases	8034097	3001893	SCOP2B (2022-06-29)
D [auth B]	SCOP2B Superfamily	His-Me finger endonucleases	8034097	3001893	SCOP2B (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
C [auth A]	zf-His_Me_endon_like	e1cz0A1	A: few secondary structure elements	X: His-Me finger endonucleases (From Homology)	H: His-Me finger endonucleases	T: His-Me finger endonucleases	F: zf-His_Me_endon_like	ECOD (1.6)
D [auth B]	zf-His_Me_endon_like	e1cz0B1	A: few secondary structure elements	X: His-Me finger endonucleases (From Homology)	H: His-Me finger endonucleases	T: His-Me finger endonucleases	F: zf-His_Me_endon_like	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
C [auth A]	3.90.75.10	Alpha Beta	Alpha-Beta Complex	Homing Intron 3 (I-Ppo) Encoded Endonuclease	Chain A	CATH (4.3.0)
D [auth B]	3.90.75.10	Alpha Beta	Alpha-Beta Complex	Homing Intron 3 (I-Ppo) Encoded Endonuclease	Chain A	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
C [auth A], D [auth B]	PF05551	Zinc-binding loop region of homing endonuclease (zf-His_Me_endon)	Zinc-binding loop region of homing endonuclease	This domain [1] is the short zinc-binding loops region of a number of much longer chain homing endonucleases. Such loops are probably stabilised by the zinc and may be viewed as small but separate domains. The common structural feature of these domai ...	This domain [1] is the short zinc-binding loops region of a number of much longer chain homing endonucleases. Such loops are probably stabilised by the zinc and may be viewed as small but separate domains. The common structural feature of these domains is that at least three zinc ligands lie very close to each other in the sequence and are not incorporated into regular secondary structural elements. The biological roles played by these small zinc-binding domains are presently unknown [2].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A [auth C], B [auth D]	DNA (5'-D(TPTPGPAPCPTPCPTPCPTPTPAPAPGPAPGPAPGPTPCP*A)-3')	-	-	-
C [auth A], D [auth B]	INTRON-ENCODED HOMING ENDONUCLEASE I-PPOI	endonuclease activity nuclease activity catalytic activity, acting on a nucleic acid catalytic activity	nucleobase-containing compound metabolic process DNA recombination metabolic process cellular process primary metabolic process DNA metabolic process macromolecule metabolic process nucleic acid metabolic process intron homing	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
C [auth A], D [auth B]	IPR008704	Zinc-binding loop region of homing endonuclease	Domain
C [auth A], D [auth B]	IPR044930	Homing endonuclease, His-Me finger superfamily	Homologous Superfamily
C [auth A], D [auth B]	IPR044925	His-Me finger superfamily	Homologous Superfamily

Structure Motif Annotation: Mechanism and Catalytic Site Atlas M-CSA Database Homepage

Chains	Enzyme Name	Description	Catalytic Residues
C [auth A]	intron-encoded endonuclease I-PpoI M-CSA #837	I-PpoI is a homing endonuclease of the His-Cys family. It is encoded by the nuclear 26S rRNA gene of Physarum polycephalum and cleaves a 16bp homing site to generate four-base 3' overhangs. It requires divalent metal cations, but a wide range are accommodated.	Defined by 4 residues: ARG:C-60 [auth A-61]HIS:C-97 [auth A-98]CYS:C-104 [auth A-105]ASN:C-118 [auth A-119] \| Explore in 3D: M-CSA Motif Definition Search M-CSA Motif EC: 3.1 (PDB Primary Data) Search M-CSA Motif + EC 3.1

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.