9PXP: Fem-1 homolog B

Name: PDB 9PXP: Fem-1 homolog B (FEM1B) in complex with VU0416476
Published: 2025-11-26
License: https://creativecommons.org/publicdomain/zero/1.0/
Keywords: ligase

Fem-1 homolog B (FEM1B) in complex with VU0416476. Determined by X-ray diffraction at 3.0 Å resolution. Released 26 Nov 2025.

Method: X-ray diffraction
Resolution: 3.0 Å
Organism: Homo sapiens
Chains: 2
Atoms: 4,798
Mol. weight: 78.81 kDa
Ligands: A1CMY
Released: 26 Nov 2025

Explore 9PXP in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9PXP contains 39 α-helices and 10 β-strands across 2 chains. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 19 helices, 4 β-strands

Element	Residues	Length	Sheet
α-helix	1-14	14
α-helix	17-24	8
α-helix	29-37	9
β-strand	40-42	3	1
β-strand	45-47	3	1
α-helix	49-56	8
α-helix	59-67	9
β-strand	76-81	6	2
β-strand	84-90	7	2
α-helix	91-97	7
α-helix	101-109	9
α-helix	124-131	8
α-helix	134-142	9
α-helix	157-163	7
α-helix	167-175	9
α-helix	190-197	8
α-helix	200-208	9
α-helix	222-228	7
α-helix	232-239	8
α-helix	247-262	16
α-helix	269-282	14
α-helix	311-315	5
α-helix	321-336	16

Chain B: 20 helices, 6 β-strands

Element	Residues	Length	Sheet
α-helix	1-13	13
α-helix	17-24	8
α-helix	29-37	9
β-strand	40-42	3	3
β-strand	45-47	3	3
α-helix	49-55	7
α-helix	59-62	4
α-helix	63-68	6
β-strand	76-80	5	4
β-strand	85-90	6	4
α-helix	91-97	7
α-helix	101-109	9
α-helix	124-131	8
α-helix	134-142	9
α-helix	152-154	3
α-helix	157-164	8
α-helix	167-173	7
α-helix	190-197	8
α-helix	200-205	6
β-strand	209	1	5
β-strand	211	1	5
α-helix	224-227	4
α-helix	232-240	9
α-helix	256-262	7
α-helix	269-283	15
α-helix	323-335	13

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Protein fem-1 homolog B	A, B	protein	357	Homo sapiens	Q9UK73 (AlphaFold model)

Sequence of entity 1 (A, B), FASTA

>9PXP_1 Protein fem-1 homolog B (chains A, B)
GHMEGLAGYVYKAASEGKVLTLAALLLNRSESDIRYLLGYVSQQGGQRSTPLIIAARNGH
AKVVRLLLEHYRVQTQQTGTVRFDGYVIDGATALWCAAGAGHFEVVKLLVSHGANVNHTT
VTNSTPLRAACFDGRLDIVKYLVENNANISIANKYDNTCLMIAAYKGHTDVVRYLLEQRA
DPNAKAHCGATALHFAAEAGHIDIVKELIKWRAAIVVNGHGMTPLKVAAESCKADVVELL
LSHADCDRRSRIEALELLGASFANDRENYDIIKTYHYLYLAMLERFQDGDNILEKEVLPP
IHAYGNRTECRNPQELESIRQDRDALHMEGLIVRERILGGGGSGGGSKKRLLLGLDR

Ligands and cofactors

ID	Name	Formula	Copies
A1CMY	2-tert-butyl-4,5-dichloropyridazin-3(2H)-one	C8 H10 Cl2 N2 O	1

Primary citation

Nuclear Magnetic Resonance-based fragment screen of the E3 ligase Fem-1 homolog B. Katinas, J.M., Amporndanai, K., Taylor, A.J. et al. Protein Sci (2025) 34:e70365-e70365. DOI 10.1002/pro.70365 · PubMed

Other PDB entries of the same protein (UniProt Q9UK73 (AlphaFold model), which also has an AlphaFold model), best resolution first:

9PW8 2.8 Å, Fem-1 homolog B (FEM1B) in complex with VU0417412
7EL6 2.8 Å, Structure of SMCR8 bound FEM1B
9PQA 2.9 Å, Fem-1 homolog B (FEM1B) in complex with VU0432623
9PQ9 2.93 Å, Fem-1 homolog B (FEM1B) in complex with VU0421763
9PWJ 3.0 Å, Fem-1 homolog B (FEM1B) in complex with VU0081201
9PXO 3.05 Å, Fem-1 homolog B (FEM1B) in complex with VU0023775
9PQE 3.1 Å, Fem-1 homolog B (FEM1B) in complex with VU0412674
6LBF 3.25 Å, Crystal structure of FEM1B
8WQF 3.27 Å, cryo-EM structure of CUL2-RBX1-ELOB-ELOC-FEM1B bound with the C-degron of CUX1…
8WQB 3.37 Å, Cryo-EM structure of CUL2-RBX1-ELOB-ELOC-FEM1B bound with the C-degron of CCDC89…
8WQE 3.38 Å, Cryo-EM structure of CUL2-RBX1-ELOB-ELOC-FEM1B bound with the C-degron of CUX1…
8WQA 3.39 Å, Cryo-EM structure of CUL2-RBX1-ELOB-ELOC-FEM1B bound with the C-degron of CCDC89…

Browse structure collections

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