1H3B

Squalene-Hopene Cyclase

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: SCOP2 Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Structure Motif: Primary M-CSA Annotation

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1h3ba1	All alpha proteins	alpha/alpha toroid	Terpenoid cyclases/Protein prenyltransferases	Terpene synthases	Squalene-hopene cyclase	(Alicyclobacillus acidocaldarius ) [TaxId: 405212 ],	SCOPe (2.08)
B	d1h3bb1	All alpha proteins	alpha/alpha toroid	Terpenoid cyclases/Protein prenyltransferases	Terpene synthases	Squalene-hopene cyclase	(Alicyclobacillus acidocaldarius ) [TaxId: 405212 ],	SCOPe (2.08)
C	d1h3bc1	All alpha proteins	alpha/alpha toroid	Terpenoid cyclases/Protein prenyltransferases	Terpene synthases	Squalene-hopene cyclase	(Alicyclobacillus acidocaldarius ) [TaxId: 405212 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038394	3001024	SCOP2B (2022-06-29)
A	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038392	3001024	SCOP2B (2022-06-29)
A	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038392	3001024	SCOP2B (2022-06-29)
B	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038392	3001024	SCOP2B (2022-06-29)
B	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038394	3001024	SCOP2B (2022-06-29)
B	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038392	3001024	SCOP2B (2022-06-29)
C	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038392	3001024	SCOP2B (2022-06-29)
C	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038392	3001024	SCOP2B (2022-06-29)
C	SCOP2B Superfamily	Terpenoid cyclases/Protein prenyltransferases	8038394	3001024	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)
A	PF13243	e1h3bA1	A: alpha superhelices	X: Repetitive alpha hairpins	H: alpha/alpha toroid (From Topology)	T: alpha/alpha toroid	F: PF13243	ECOD (1.6)
A	PF13249	e1h3bA2	A: alpha superhelices	X: Repetitive alpha hairpins	H: alpha/alpha toroid (From Topology)	T: alpha/alpha toroid	F: PF13249	ECOD (1.6)
B	PF13243	e1h3bB1	A: alpha superhelices	X: Repetitive alpha hairpins	H: alpha/alpha toroid (From Topology)	T: alpha/alpha toroid	F: PF13243	ECOD (1.6)
B	PF13249	e1h3bB2	A: alpha superhelices	X: Repetitive alpha hairpins	H: alpha/alpha toroid (From Topology)	T: alpha/alpha toroid	F: PF13249	ECOD (1.6)
C	PF13243	e1h3bC1	A: alpha superhelices	X: Repetitive alpha hairpins	H: alpha/alpha toroid (From Topology)	T: alpha/alpha toroid	F: PF13243	ECOD (1.6)
C	PF13249	e1h3bC2	A: alpha superhelices	X: Repetitive alpha hairpins	H: alpha/alpha toroid (From Topology)	T: alpha/alpha toroid	F: PF13249	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	1.50.10.20	Mainly Alpha	Alpha/alpha barrel	Glycosyltransferase		CATH (4.3.0)
B	1.50.10.20	Mainly Alpha	Alpha/alpha barrel	Glycosyltransferase		CATH (4.3.0)
C	1.50.10.20	Mainly Alpha	Alpha/alpha barrel	Glycosyltransferase		CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B, C	PF13243	Squalene-hopene cyclase C-terminal domain (SQHop_cyclase_C)	Squalene-hopene cyclase C-terminal domain	-	Repeat
A, B, C	PF00432	Prenyltransferase and squalene oxidase repeat (Prenyltrans)	Prenyltransferase and squalene oxidase repeat	-	Repeat

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B, C	SQUALENE--HOPENE CYCLASE	lyase activity catalytic activity squalene cyclase activity isomerase activity squalene-hopene cyclase activity cyclase activity intramolecular transferase activity	triterpenoid biosynthetic process triterpenoid metabolic process isoprenoid biosynthetic process cellular biosynthetic process cellular metabolic process lipid biosynthetic process primary metabolic process terpenoid biosynthetic process organic substance metabolic process biosynthetic process cellular lipid metabolic process organic substance biosynthetic process metabolic process cellular process triterpenoid biosynthetic process triterpenoid metabolic process isoprenoid biosynthetic process cellular biosynthetic process cellular metabolic process lipid biosynthetic process primary metabolic process terpenoid biosynthetic process organic substance metabolic process biosynthetic process cellular lipid metabolic process organic substance biosynthetic process metabolic process cellular process terpenoid metabolic process isoprenoid metabolic process lipid metabolic process	cell periphery plasma membrane membrane cellular anatomical entity lipid droplet intracellular organelle intracellular anatomical structure organelle intracellular non-membrane-bounded organelle non-membrane-bounded organelle

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B, C	IPR032697	Squalene cyclase, N-terminal	Domain
A, B, C	IPR032696	Squalene cyclase, C-terminal	Domain
A, B, C	IPR018333	Squalene cyclase	Family
A, B, C	IPR002365	Terpene synthase, conserved site	Conserved Site
A, B, C	IPR008930	Terpenoid cyclases/protein prenyltransferase alpha-alpha toroid	Homologous Superfamily
A, B, C	IPR006400	Squalene hopene cyclase	Family

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

Chains	Enzyme Name	Description	Catalytic Residues
A	squalene-hopene cyclase M-CSA #254	Squalene-hopene cyclase (SHC) from Alicyclobacillus acidocaldarius catalyses the cyclisation of linear triterpene squalene. There are two possible products; hop-22(29)-ene or hopan-22-ol (aka diplopterol) which are formed in a roughly 90:10 ratio. SHC is a membrane protein with characteristics similar to those of prostaglandin-H2 synthase, the only other reported protein of this type. Enzymes like SHC are the targets for the development of anticholesteremic and antifungal drugs.	Defined by 17 residues: GLU:A-45GLU:A-93ARG:A-127TRP:A-169GLN:A-262TRP:A-312PHE:A-365ASP:A-374ASP:A-376ASP:A-377TYR:A-420HIS:A-451TRP:A-489TYR:A-495PHE:A-601PHE:A-605TYR:A-609 \| Explore in 3D: M-CSA Motif Definition Up to 10 residues are supported for Structure Motif searching, this motif has 17 residues. EC: 5.4.99.17 (PDB Primary Data)

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 R01GM133198.