6Y9B | pdb_00006y9b

Cryo-EM structure of trimeric human STEAP1 bound to three Fab120.545 fragments

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: ECOD Classification
IMGT Antibody Annotation
SAbDab Antibody Annotation
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations
Membrane Protein Annotation: OPM
Membrane Protein Annotation: PDBTM
Membrane Protein Annotation: MemProtMD
Membrane Protein Annotation: mpstruc

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
E [auth J]	d6y9bj_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
D [auth I]	d6y9bi_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
C [auth H]	d6y9bh_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
G [auth N]	d6y9bn_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
F [auth M]	d6y9bm_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)
B [auth L]	d6y9bl_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	house mouse (Mus musculus ) [TaxId: 10090 ],	SCOPe (2.08)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
E [auth J]		e6y9bJ1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)
D [auth I]		e6y9bI1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)
C [auth H]		e6y9bH1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)
G [auth N]		e6y9bN1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)
F [auth M]		e6y9bM1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)
B [auth L]		e6y9bL1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)
I [auth B]		e6y9bB1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)
H [auth A]		e6y9bA1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)
A [auth C]		e6y9bC1	A: Family A G protein-coupled receptor-like	X: Family A G protein-coupled receptor-like	H: Family A G protein-coupled receptor-like	T: Bac_rhodopsin	F:	ECOD (20:10:01)

IMGT Antibody Annotation IMGT Database Homepage

Chain	Protein Name	Description	Organism Name	Gene Allele Name(s)	Domain Name(s)	Receptor Type	Receptor Description	Provenance Source
C [auth H], D [auth I], E [auth J]	Fab120.545, anti-steap1	VH-CH1	Homo sapiens (human)	IGHV3-202, IGHJ201, IGHG103, IGHG108, IGHG1*06	V-DOMAIN VH, C-DOMAIN CH1	IG	FAB-GAMMA-1_KAPPA	IMGT (202609-0)
B [auth L], F [auth M], G [auth N]	Fab120.545, anti-steap1	L-KAPPA	Homo sapiens (human)	IGKV8-3001, IGKJ101, IGKJ201, IGKC01	V-DOMAIN V-KAPPA, C-DOMAIN C-KAPPA	IG	FAB-GAMMA-1_KAPPA	IMGT (202609-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
C [auth H], D [auth I], E [auth J]	Heavy Chain	IGHV3	-	metalloreductase steap1	SAbDab (2026-03-13)
B [auth L], F [auth M], G [auth N]	Light Chain	IGKV8	Kappa	metalloreductase steap1	SAbDab (2026-03-13)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A [auth C], H [auth A], I [auth B]	PF01794	Ferric reductase like transmembrane component (Ferric_reduct)	Ferric reductase like transmembrane component	This family includes a common region in the transmembrane proteins mammalian cytochrome B-245 heavy chain (gp91-phox), ferric reductase transmembrane component in yeast and respiratory burst oxidase from mouse-ear cress. This may be a family of flavo ...	This family includes a common region in the transmembrane proteins mammalian cytochrome B-245 heavy chain (gp91-phox), ferric reductase transmembrane component in yeast and respiratory burst oxidase from mouse-ear cress. This may be a family of flavocytochromes capable of moving electrons across the plasma membrane [1]. The Frp1 protein Swiss:Q04800 from S. pombe is a ferric reductase component and is required for cell surface ferric reductase activity, mutants in frp1 are deficient in ferric iron uptake [1]. Cytochrome B-245 heavy chain Swiss:P04839 is a FAD-dependent dehydrogenase it is also has electron transferase activity which reduces molecular oxygen to superoxide anion, a precursor in the production of microbicidal oxidants [2]. Mutations in the sequence of cytochrome B-245 heavy chain (gp91-phox) lead to the X-linked chronic granulomatous disease. The bacteriocidal ability of phagocytic cells is reduced and is characterised by the absence of a functional plasma membrane associated NADPH oxidase [3]. The chronic granulomatous disease gene codes for the beta chain of cytochrome B-245 and cytochrome B-245 is missing from patients with the disease [4].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
C [auth H], D [auth I], E [auth J]	Fab120.545 heavy chain	-	-	-
B [auth L], F [auth M], G [auth N]	Fab120.545 light chain	-	-	-
A [auth C], H [auth A], I [auth B]	Metalloreductase STEAP1	binding tetrapyrrole binding heme binding cation binding ion binding metal ion binding small molecule binding	-	endosome membrane membrane-bounded organelle intracellular anatomical structure membrane endosome intracellular vesicle intracellular membrane-bounded organelle endomembrane system intracellular organelle cytoplasmic vesicle membrane cellular anatomical structure bounding membrane of organelle vesicle membrane cytoplasmic vesicle endosome membrane membrane-bounded organelle intracellular anatomical structure membrane endosome intracellular vesicle intracellular membrane-bounded organelle endomembrane system intracellular organelle cytoplasmic vesicle membrane cellular anatomical structure bounding membrane of organelle vesicle membrane cytoplasmic vesicle organelle cytoplasm vesicle organelle membrane cell periphery plasma membrane cell-cell junction anchoring junction cell junction

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A [auth C], H [auth A], I [auth B]	IPR013130	Ferric reductase transmembrane component-like domain	Domain
A [auth C], H [auth A], I [auth B]	IPR051267	STEAP family metalloreductases	Family

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A [auth C], H [auth A], I [auth B]	Pharos: Q9UHE8	astrocytic tumor cystic fibrosis gastric carcinoma malignant ependymoma malignant pancreatic neoplasm osteosarcoma pancreatic intraductal papillary-mucinous neoplasm with low grade dysplasia atopic eczema ductal breast carcinoma in situ glioblastoma malignant glioma non-small cell lung carcinoma ovarian cancer atypical teratoid rhabdoid tumor esophageal adenocarcinoma astrocytic tumor cystic fibrosis gastric carcinoma malignant ependymoma malignant pancreatic neoplasm osteosarcoma pancreatic intraductal papillary-mucinous neoplasm with low grade dysplasia atopic eczema ductal breast carcinoma in situ glioblastoma malignant glioma non-small cell lung carcinoma ovarian cancer atypical teratoid rhabdoid tumor esophageal adenocarcinoma lung adenocarcinoma malignant mesothelioma oligodendroglioma pancreatic intraductal papillary-mucinous neoplasm

Membrane Protein Annotation: OPM OPM Database Homepage

Chains	External Link	Type	Class	Superfamily	Family
A [auth C], H [auth A], I [auth B]	OPM	Transmembrane	Alpha-helical polytopic	Electron transport chain complex II superfamily	Transmembrane ferric reductase

Membrane Protein Annotation: PDBTM PDBTM Database Homepage

Chains	External Link	Comment
A [auth C], H [auth A], I [auth B]	PDBTM	Annotated as membrane protein by PDBTM

Membrane Protein Annotation: MemProtMD MemProtMD Database Homepage

Chains	External Link	Comment
A [auth C], H [auth A], I [auth B]	MemProtMD	Annotated as membrane protein by MemProtMD

Membrane Protein Annotation: mpstruc mpstruc Database Homepage

Chains	Resource Link	Group	Subgroup	Protein
A [auth C], H [auth A], I [auth B]	mpstruc	TRANSMEMBRANE PROTEINS: ALPHA-HELICAL	Oxidoreductases	STEAP1 (Six-Transmembrane Epithelial Antigen of the Prostate1) bound to three Fab120.545 fragments

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.