7TAI

Structure of STEAP2 in complex with ligands

  • Classification: OXIDOREDUCTASE
  • Organism(s): Homo sapiens
  • Expression System: Trichoplusia ni
  • Mutation(s): No 

  • Deposited: 2021-12-20 Released: 2023-01-25 
  • Deposition Author(s): Wang, L., Chen, K.H., Zhou, M.
  • Funding Organization(s): National Institutes of Health/Eunice Kennedy Shriver National Institute of Child Health & Human Development (NIH/NICHD)

Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.20 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Mechanism of stepwise electron transfer in six-transmembrane epithelial antigen of the prostate (STEAP) 1 and 2.

Chen, K.Wang, L.Shen, J.Tsai, A.L.Zhou, M.Wu, G.

(2023) Elife 12

  • DOI: https://doi.org/10.7554/eLife.88299
  • Primary Citation of Related Structures:  
    7TAI

  • PubMed Abstract: 

    Six transmembrane epithelial antigen of the prostate (STEAP) 1-4 are membrane-embedded hemoproteins that chelate a heme prosthetic group in a transmembrane domain (TMD). STEAP2-4, but not STEAP1, have an intracellular oxidoreductase domain (OxRD) and can mediate cross-membrane electron transfer from NADPH via FAD and heme. However, it is unknown whether STEAP1 can establish a physiologically relevant electron transfer chain. Here, we show that STEAP1 can be reduced by reduced FAD or soluble cytochrome b 5 reductase that serves as a surrogate OxRD, providing the first evidence that STEAP1 can support a cross-membrane electron transfer chain. It is not clear whether FAD, which relays electrons from NADPH in OxRD to heme in TMD, remains constantly bound to the STEAPs. We found that FAD reduced by STEAP2 can be utilized by STEAP1, suggesting that FAD is diffusible rather than staying bound to STEAP2. We determined the structure of human STEAP2 in complex with NADP + and FAD to an overall resolution of 3.2 Å by cryo-electron microscopy and found that the two cofactors bind STEAP2 similarly as in STEAP4, suggesting that a diffusible FAD is a general feature of the electron transfer mechanism in the STEAPs. We also demonstrated that STEAP2 reduces ferric nitrilotriacetic acid (Fe 3+ -NTA) significantly slower than STEAP1 and proposed that the slower reduction is due to the poor Fe 3+ -NTA binding to the highly flexible extracellular region in STEAP2. These results establish a solid foundation for understanding the function and mechanisms of the STEAPs.


  • Organizational Affiliation

    Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, United States.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Metalloreductase STEAP2A [auth B],
B [auth A],
C
490Homo sapiensMutation(s): 0 
Gene Names: STEAP2PCANAP1STAMP1UNQ6507/PRO23203
EC: 1.16.1
UniProt & NIH Common Fund Data Resources
Find proteins for Q8NFT2 (Homo sapiens)
Go to UniProtKB:  Q8NFT2
PHAROS:  Q8NFT2
GTEx:  ENSG00000157214 
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 5 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
FAD (Subject of Investigation/LOI)
Query on FAD

Download Ideal Coordinates CCD File 
D [auth B],
J [auth A],
P [auth C]
FLAVIN-ADENINE DINUCLEOTIDE
C27 H33 N9 O15 P2
VWWQXMAJTJZDQX-UYBVJOGSSA-N
LBN
Query on LBN

Download Ideal Coordinates CCD File 
G [auth B],
M [auth A],
S [auth C]
1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine
C42 H82 N O8 P
WTJKGGKOPKCXLL-VYOBOKEXSA-N
NAP (Subject of Investigation/LOI)
Query on NAP

Download Ideal Coordinates CCD File 
F [auth B],
L [auth A],
R [auth C]
NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE
C21 H28 N7 O17 P3
XJLXINKUBYWONI-NNYOXOHSSA-N
HEM (Subject of Investigation/LOI)
Query on HEM

Download Ideal Coordinates CCD File 
E [auth B],
K [auth A],
Q [auth C]
PROTOPORPHYRIN IX CONTAINING FE
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
CLR
Query on CLR

Download Ideal Coordinates CCD File 
H [auth B]
I [auth B]
N [auth A]
O [auth A]
T [auth C]
H [auth B],
I [auth B],
N [auth A],
O [auth A],
T [auth C],
U [auth C]
CHOLESTEROL
C27 H46 O
HVYWMOMLDIMFJA-DPAQBDIFSA-N
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.20 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/Eunice Kennedy Shriver National Institute of Child Health & Human Development (NIH/NICHD)United States--

Revision History  (Full details and data files)

  • Version 1.0: 2023-01-25
    Type: Initial release
  • Version 1.1: 2024-02-07
    Changes: Data collection, Database references