1NQF: Vitamin B12 receptor

Outer membrane cobalamin transporter (BTUB) from E. Coli, methionine substiution construct for se-met sad phasing. Determined by X-ray diffraction at 2.7 Å resolution. Released 29 Apr 2003.

Method: X-ray diffraction
Resolution: 2.7 Å
Organism: Escherichia coli
Chains: 1
Atoms: 4,490
Mol. weight: 68.53 kDa
Ligands: C8E, MG
Released: 29 Apr 2003

Explore 1NQF in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

1NQF contains 8 α-helices and 35 β-strands across 1 chain. 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: 8 helices, 35 β-strands

Element	Residues	Length	Sheet
β-strand	8-9	2	1
β-strand	17-18	2	1
α-helix	19-21	3
β-strand	26-30	5	2
α-helix	31-37	7
β-strand	52-56	5	3
β-strand	64-68	5	3
β-strand	77-80	4	2
β-strand	84	1	2
α-helix	101-103	3
β-strand	106-111	6	2
α-helix	115-118	4
β-strand	125-130	6	2
β-strand	137-145	9	4
β-strand	150-158	9	4
β-strand	164-174	11	4
β-strand	197-209	13	4
β-strand	214-227	14	4
β-strand	243-257	15	4
β-strand	261-276	16	4
β-strand	289-305	17	4
β-strand	309-322	14	4
β-strand	333-347	15	4
β-strand	351-362	12	4
β-strand	366-380	15	4
β-strand	383-394	12	4
α-helix	395-397	3
α-helix	398-402	5
β-strand	406	1	5
α-helix	410-412	3
β-strand	413-426	14	4
β-strand	429-446	18	4
β-strand	453-471	19	4
β-strand	475-488	14	4
β-strand	494	1	4
β-strand	501-510	10	4
β-strand	515-523	9	4
β-strand	526-530	5	6
α-helix	536	1
β-strand	537-541	5	6
β-strand	544-554	11	4
β-strand	560-565	6	4
β-strand	586-593	8	4

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Vitamin B12 receptor	A	protein	594	Escherichia coli	P06129 (AlphaFold model)

Sequence of entity 1 (A), FASTA

>1NQF_1 Vitamin B12 receptor (chains A)
QDTSPDTLVVTANRFEQPRSTVLAPTTVVTRQDIDRWQSTSVNDVLRRLPGVDITQNGGS
GQLSSIFIRGTNASHVLVLIDGVRLNLAGVSGSADLSQFPIALVQRVEYIRGPRSAVYGS
DAIGGVVNIITTRDEPGTEISAGWGSNSYQNYDVSTQQQLGDKTRVTLLGDYAHTHGYDV
VAYGNTGTQAQTDNDGFLSKTLYGALEHNFTDAWSGFVRGYGYDNRTNYDAYYSPGSPLL
DTRKLYSQSWDAGLRYNGELIKSQLITSYSHSKDYNYDPHYGRYDSSATLDEMKQYTVQW
ANNVIVGHGSIGAGVDMQMQMTTPGTGYVEDGYDQRNTGIYLTGLQQVGDFTFEGAARSD
DNSQFGRHGTWQTSAGWEFIEGYRFIASYGTSYKAPNLGQLYGFYGNPNLDPEKSKQWEG
AFEGLTAGVNWRISGYRNDVSDLIDYDDHTLKYYNEGKARIKGVEATANFDTGPLTHTVS
YDYVDARNAITDTPLLRRAKQQVKYQLDWQLYDFDMGMTMQYLGTRYDKDYSSYPYQTVK
MGGVSLWDLAVAYPVTSHLTVRGKIANLFDKDYETVYGYQTAGREYTLSGSYTF

Ligands and cofactors

ID	Name	Formula	Copies
C8E	(hydroxyethyloxy)tri(ethyloxy)octane	C16 H34 O5	6
MG	Magnesium ion	Mg	1

Primary citation

Substrate-induced transmembrane signaling in the cobalamin transporter BtuB. CHIMENTO, D.P., MOHANTY, A.K., KADNER, R.J. et al. Nat Struct Biol (2003) 10:394-401. DOI 10.1038/nsb914 · PubMed

Other PDB entries of the same protein (UniProt P06129 (AlphaFold model), which also has an AlphaFold model), best resolution first:

2GUF 1.95 Å, In meso crystal structure of the cobalamin transporter, BtuB
1NQE 2.0 Å, Outer membrane cobalamin transporter (BTUB) from E. Coli
2GSK 2.1 Å, Structure of the BtuB:TonB Complex
3RGN 2.3 Å, Crystal structure of spin-labeled BtuB W371R1
3M8B 2.44 Å, Crystal structure of spin-labeled BtuB V10R1 in the apo state
3M8D 2.44 Å, Crystal structure of spin-labeled BtuB V10R1 with bound calcium and cyanocobalamin
3RGM 2.6 Å, Crystal structure of spin-labeled BtuB T156R1
1UJW 2.75 Å, Structure of the complex between BtuB and Colicin E3 Receptor binding domain
1NQH 3.1 Å, Outer membrane cobalamin transporter (BTUB) from E. Coli, with bound calcium and…
1NQG 3.31 Å, Outer membrane cobalamin transporter (BTUB) from E. Coli, with bound calcium
2YSU 3.5 Å, Structure of the complex between BtuB and Colicin E2 receptor binding domain
7NSU 4.7 Å, ColicinE9 intact translocation complex

Browse structure collections

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