4XX1 | pdb_00004xx1

Low resolution structure of LCAT in complex with Fab1

External Resource: Annotation

Domain Annotation: ECOD Classification
Domain Annotation: CATH
SAbDab Antibody Annotation
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
C [auth A]		e4xx1A1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Class I glutamine amidotransferase-like	T: Phosphodiest, Metalloenzyme	F:	ECOD (20:10:01)
F [auth B]		e4xx1B1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Class I glutamine amidotransferase-like	T: Ribos_L4_asso_C	F:	ECOD (20:10:01)
I [auth J]		e4xx1J1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Class I glutamine amidotransferase-like	T: Phosphodiest, Metalloenzyme	F:	ECOD (20:10:01)
B [auth H]		e4xx1H1	A: amino-terminal domain of OmpATb	X: amino-terminal domain of OmpATb	H: amino-terminal domain of OmpATb	T: Cytochrom_C1	F:	ECOD (20:10:01)
B [auth H]		e4xx1H2	A: Lipocalins/Streptavidin	X: SAM/DNA-glycosylase	H: SAM domain-like	T: EF-hand_1, EF-hand_6, EF-hand_7	F:	ECOD (20:10:01)
H [auth M]		e4xx1M1	A: amino-terminal domain of OmpATb	X: amino-terminal domain of OmpATb	H: amino-terminal domain of OmpATb	T: Cytochrom_C1	F:	ECOD (20:10:01)
E		e4xx1E1	A: amino-terminal domain of OmpATb	X: amino-terminal domain of OmpATb	H: amino-terminal domain of OmpATb	T: Cytochrom_C1	F:	ECOD (20:10:01)
E		e4xx1E2	A: Lipocalins/Streptavidin	X: SAM/DNA-glycosylase	H: SAM domain-like	T: EF-hand_1, EF-hand_6, EF-hand_7	F:	ECOD (20:10:01)
A [auth L]		e4xx1L1	A: amino-terminal domain of OmpATb	X: amino-terminal domain of OmpATb	H: amino-terminal domain of OmpATb	T: Cytochrom_C1	F:	ECOD (20:10:01)
D [auth G]		e4xx1G1	A: amino-terminal domain of OmpATb	X: amino-terminal domain of OmpATb	H: amino-terminal domain of OmpATb	T: Cytochrom_C1	F:	ECOD (20:10:01)
G [auth O]		e4xx1O1	A: amino-terminal domain of OmpATb	X: amino-terminal domain of OmpATb	H: amino-terminal domain of OmpATb	T: Cytochrom_C1	F:	ECOD (20:10:01)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
C [auth A]	3.40.50.1820	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	Alpha/Beta hydrolase fold, catalytic domain	CATH (4.3.0)
F [auth B]	3.40.50.1820	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	Alpha/Beta hydrolase fold, catalytic domain	CATH (4.3.0)
I [auth J]	3.40.50.1820	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	Alpha/Beta hydrolase fold, catalytic domain	CATH (4.3.0)
B [auth H]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
H [auth M]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
E	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
A [auth L]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
D [auth G]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
G [auth O]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
B [auth H], E, H [auth M]	Heavy Chain	IGHV3	-	phosphatidylcholine-sterol acyltransferase	SAbDab (2026-03-13)
A [auth L], D [auth G], G [auth O]	Light Chain	IGLV3	Lambda	phosphatidylcholine-sterol acyltransferase	SAbDab (2026-03-13)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
C [auth A], F [auth B], I [auth J]	PF02450	Lecithin:cholesterol acyltransferase (LCAT)	Lecithin:cholesterol acyltransferase	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
C [auth A], F [auth B], I [auth J]	Phosphatidylcholine-sterol acyltransferase	phospholipase activity A2-type glycerophospholipase activity hydrolase activity, acting on ester bonds glycerophospholipase activity carboxylic ester hydrolase activity hydrolase activity catalytic activity lipase activity sterol ester esterase activity apolipoprotein binding protein binding binding apolipoprotein A-I binding platelet-activating factor acetyltransferase activity phospholipase activity A2-type glycerophospholipase activity hydrolase activity, acting on ester bonds glycerophospholipase activity carboxylic ester hydrolase activity hydrolase activity catalytic activity lipase activity sterol ester esterase activity apolipoprotein binding protein binding binding apolipoprotein A-I binding platelet-activating factor acetyltransferase activity acetyltransferase activity acyltransferase activity acyltransferase activity, transferring groups other than amino-acyl groups transferase activity O-acyltransferase activity phosphatidylcholine-sterol O-acyltransferase activity 1-alkyl-2-acetylglycerophosphocholine esterase activity	biosynthetic process lipoprotein biosynthetic process lipoprotein metabolic process metabolic process cellular process primary metabolic process macromolecule metabolic process protein metabolic process macromolecule biosynthetic process response to copper ion response to stimulus response to metal ion response to chemical glycerophospholipid biosynthetic process biosynthetic process lipoprotein biosynthetic process lipoprotein metabolic process metabolic process cellular process primary metabolic process macromolecule metabolic process protein metabolic process macromolecule biosynthetic process response to copper ion response to stimulus response to metal ion response to chemical glycerophospholipid biosynthetic process glycerophospholipid metabolic process lipid biosynthetic process phospholipid biosynthetic process phospholipid metabolic process glycerolipid biosynthetic process organophosphate metabolic process organophosphate biosynthetic process phosphate-containing compound metabolic process phosphatidylcholine metabolic process glycerolipid metabolic process phosphatidylcholine biosynthetic process phosphorus metabolic process lipid metabolic process localization transport macromolecule localization reverse cholesterol transport lipid localization cholesterol transport lipid transport sterol transport organic hydroxy compound transport establishment of localization aflatoxin metabolic process mycotoxin metabolic process toxin metabolic process secondary metabolic process plasma lipoprotein particle organization multicellular organismal process regulation of biological process protein-containing complex organization protein-containing complex remodeling protein-lipid complex organization biological regulation plasma lipoprotein particle remodeling regulation of plasma lipoprotein particle levels cellular component organization triglyceride-rich lipoprotein particle remodeling very-low-density lipoprotein particle remodeling protein-lipid complex remodeling cellular component organization or biogenesis sterol homeostasis chemical homeostasis homeostatic process cholesterol homeostasis lipid homeostasis secondary alcohol metabolic process sterol metabolic process steroid metabolic process cholesterol metabolic process alcohol metabolic process small molecule metabolic process regulation of cellular process regulation of cellular component organization regulation of high-density lipoprotein particle assembly regulation of cellular component biogenesis cellular component biogenesis regulation of protein-containing complex assembly cellular component assembly high-density lipoprotein particle assembly protein-containing complex assembly regulation of multicellular organismal process plasma lipoprotein particle assembly protein-lipid complex assembly response to corticosteroid response to lipid response to hormone response to steroid hormone response to endogenous stimulus response to glucocorticoid high-density lipoprotein particle remodeling	protein-containing complex cellular anatomical structure extracellular region plasma lipoprotein particle high-density lipoprotein particle extracellular space lipoprotein particle protein-lipid complex extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle organelle vesicle protein-containing complex cellular anatomical structure extracellular region plasma lipoprotein particle high-density lipoprotein particle extracellular space lipoprotein particle protein-lipid complex extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle organelle vesicle extracellular membrane-bounded organelle
B [auth H], E, H [auth M]	Fab1 heavy chain	-	-	-
A [auth L], D [auth G], G [auth O]	Fab1 light chain	-	-	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
C [auth A], F [auth B], I [auth J]	IPR003386	Lecithin:cholesterol/phospholipid:diacylglycerol acyltransferase	Family
C [auth A], F [auth B], I [auth J]	IPR029058	Alpha/Beta hydrolase fold	Homologous Superfamily

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
C [auth A], F [auth B], I [auth J]	Pharos: P04180	Norum disease fish eye disease astrocytic tumor glioblastoma hypolipoproteinemia malignant ependymoma pancreatic ductal adenocarcinoma cataract hepatocellular carcinoma inborn errors of metabolism metabolic syndrome X oligodendroglioma pilocytic astrocytoma Hypercholesterolemia, Familial non-small cell lung carcinoma Norum disease fish eye disease astrocytic tumor glioblastoma hypolipoproteinemia malignant ependymoma pancreatic ductal adenocarcinoma cataract hepatocellular carcinoma inborn errors of metabolism metabolic syndrome X oligodendroglioma pilocytic astrocytoma Hypercholesterolemia, Familial non-small cell lung carcinoma ovarian cancer primary biliary cholangitis

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. RCSB PDB uses resources of the National Energy Research Scientific Computing Center (NERSC), a Department of Energy User Facility.