1XG2

Crystal structure of the complex between pectin methylesterase and its inhibitor protein

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

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1xg2a_	All beta proteins	Single-stranded right-handed beta-helix	Pectin lyase-like	Pectin methylesterase	automated matches	(Solanum lycopersicum ) [TaxId: 4081 ],	SCOPe (2.08)
B	d1xg2b1	All alpha proteins	Bromodomain-like	Plant invertase/pectin methylesterase inhibitor	automated matches	automated matches	(Actinidia chinensis ) [TaxId: 3625 ],	SCOPe (2.08)
B	d1xg2b2	Artifacts	Tags	Tags	Tags	N-terminal Tags	(Actinidia chinensis ) [TaxId: 3625 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2 Family	Pectin methylesterase	8076376	4002813	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	Pectin lyase-like	8076377	3001746	SCOP2 (2022-06-29)
B	SCOP2 Family	Plant invertase/pectin methylesterase inhibitor	8065301	4000644	SCOP2 (2022-06-29)
B	SCOP2 Superfamily	Plant invertase/pectin methylesterase inhibitor	8065302	3000860	SCOP2 (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	Pectinesterase	e1xg2A1	A: beta duplicates or obligate multimers	X: Single-stranded right-handed beta-helix	H: Pectin lyase-like (From Topology)	T: Pectin lyase-like	F: Pectinesterase	ECOD (1.6)
B	PMEI	e1xg2B1	A: alpha bundles	X: Bromodomain-like	H: Plant invertase/pectin methylesterase inhibitor (From Topology)	T: Plant invertase/pectin methylesterase inhibitor	F: PMEI	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	2.160.20.10	Mainly Beta	3 Solenoid	Pectate Lyase C-like	Single-stranded right-handed beta-helix, Pectin lyase-like	CATH (4.3.0)
B	1.20.140.40	Mainly Alpha	Up-down Bundle	Butyryl-CoA Dehydrogenase, subunit A	domain 3	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF01095	Pectinesterase (Pectinesterase)	Pectinesterase	-	Repeat
B	PF04043	Plant invertase/pectin methylesterase inhibitor (PMEI)	Plant invertase/pectin methylesterase inhibitor	This domain inhibits pectin methylesterases (PMEs) and invertases through formation of a non-covalent 1:1 complex [1]. It has been implicated in the regulation of fruit development, carbohydrate metabolism and cell wall extension (see [2]). It may al ...	This domain inhibits pectin methylesterases (PMEs) and invertases through formation of a non-covalent 1:1 complex [1]. It has been implicated in the regulation of fruit development, carbohydrate metabolism and cell wall extension (see [2]). It may also be involved in inhibiting microbial pathogen PMEs. It has been observed that it is often expressed as a large inactive preprotein [1]. It is also found at the N-termini of PMEs predicted from DNA sequences (personal obs:C Yeats), suggesting that both PMEs and their inhibitor are expressed as a single polyprotein and subsequently processed. It has two disulphide bridges and is mainly alpha-helical [2].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Pectinesterase 1	pectinesterase activity hydrolase activity, acting on ester bonds carboxylic ester hydrolase activity hydrolase activity catalytic activity enzyme regulator activity molecular function inhibitor activity pectinesterase inhibitor activity molecular function regulator activity enzyme inhibitor activity	cellular component organization cell wall modification cell wall organization or biogenesis cell wall organization cellular process cellular component organization or biogenesis external encapsulating structure organization developmental process multicellular organismal process reproductive system development reproductive process developmental maturation developmental process involved in reproduction fruit ripening cellular component organization cell wall modification cell wall organization or biogenesis cell wall organization cellular process cellular component organization or biogenesis external encapsulating structure organization developmental process multicellular organismal process reproductive system development reproductive process developmental maturation developmental process involved in reproduction fruit ripening multicellular organism development fruit development anatomical structure maturation anatomical structure development reproductive structure development system development carbohydrate metabolic process galacturonan metabolic process catabolic process pectin metabolic process carbohydrate catabolic process primary metabolic process macromolecule catabolic process pectin catabolic process polysaccharide metabolic process polysaccharide catabolic process metabolic process macromolecule metabolic process	cellular anatomical structure extracellular region
B	Pectinesterase inhibitor	enzyme regulator activity molecular function inhibitor activity pectinesterase inhibitor activity molecular function regulator activity enzyme inhibitor activity	-	cellular anatomical structure intracellular anatomical structure cytoplasm

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR012334	Pectin lyase fold	Homologous Superfamily
A	IPR000070	Pectinesterase, catalytic	Domain
A	IPR018040	Pectinesterase, Tyr active site	Active Site
A	IPR006501	Pectinesterase inhibitor domain	Domain
A	IPR035513	Invertase/pectin methylesterase inhibitor domain superfamily	Homologous Superfamily
A	IPR011050	Pectin lyase fold/virulence factor	Homologous Superfamily
A	IPR033131	Pectinesterase, Asp active site	Active Site
B	IPR034086	Pectinesterase inhibitor, plant	Family
B	IPR052421	Plant Cell Wall Enzyme Inhibitor	Family
B	IPR006501	Pectinesterase inhibitor domain	Domain
B	IPR035513	Invertase/pectin methylesterase inhibitor domain superfamily	Homologous Superfamily

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.