1N4A: Vitamin B12 transport protein btuF

Name: PDB 1N4A: The Ligand Bound Structure of E.coli BtuF, the Periplasmic Binding Protein for Vitamin B12
Published: 2003-03-11
License: https://creativecommons.org/publicdomain/zero/1.0/
Keywords: transport protein

The Ligand Bound Structure of E.coli BtuF, the Periplasmic Binding Protein for Vitamin B12. Determined by X-ray diffraction at 2.0 Å resolution. Released 11 Mar 2003.

Method: X-ray diffraction
Resolution: 2.0 Å
Organism: Escherichia coli
Chains: 2
Atoms: 4,539
Mol. weight: 58.99 kDa
Ligands: CNC
Released: 11 Mar 2003

Explore 1N4A in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

1N4A contains 31 α-helices and 34 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: 17 helices, 16 β-strands

Element	Residues	Length	Sheet
β-strand	4-6	3	1
α-helix	9-17	9
β-strand	24	1	1
β-strand	25-26	2	2
α-helix	33-37	5
α-helix	39	1
β-strand	40-42	3	2
β-strand	47	1	2
α-helix	49-54	6
β-strand	59-63	5	1
β-strand	64	1	3
β-strand	67	1	3
α-helix	69-72	4
α-helix	74-77	4
β-strand	82-85	4	1
α-helix	90-100	11
α-helix	101-103	3
α-helix	107-128	22
α-helix	132-133	2
β-strand	134-138	5	4
β-strand	140	1	5
β-strand	146	1	5
α-helix	153-160	8
β-strand	163-165	3	4
β-strand	176	1	5
α-helix	179-184	6
β-strand	189-192	4	4
α-helix	196-198	3
α-helix	199-206	8
α-helix	207-209	3
β-strand	214-216	3	4
α-helix	219-222	4
α-helix	229-240	12

Chain B: 14 helices, 18 β-strands

Element	Residues	Length	Sheet
β-strand	5004-5006	3	6
α-helix	5009-5017	9
β-strand	5024	1	6
β-strand	5025-5026	2	7
α-helix	5033-5037	5
α-helix	5039	1
β-strand	5040-5043	4	7
β-strand	5046-5047	2	7
α-helix	5049-5054	6
β-strand	5059-5063	5	6
β-strand	5064	1	8
β-strand	5067	1	8
α-helix	5069-5077	9
β-strand	5082-5085	4	6
α-helix	5090-5100	11
α-helix	5101-5103	3
α-helix	5107-5128	22
β-strand	5134-5138	5	9
β-strand	5140	1	10
β-strand	5146	1	10
α-helix	5153-5160	8
β-strand	5163-5165	3	9
β-strand	5176	1	10
α-helix	5179-5184	6
β-strand	5189-5192	4	9
β-strand	5194	1	11
α-helix	5196-5198	3
α-helix	5199-5206	8
β-strand	5214-5216	3	9
β-strand	5218	1	11
α-helix	5219-5222	4
α-helix	5229-5240	12

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Vitamin B12 transport protein btuF	A, B	protein	252	Escherichia coli	P37028 (AlphaFold model)

Sequence of entity 1 (A, B), FASTA

>1N4A_1 Vitamin B12 transport protein btuF (chains A, B)
APRVITLSPANTELAFAAGITPVGVSSYSDYPPQAQKIEQVSTWQGMNLERIVALKPDLV
IAWRGGNAERQVDQLASLGIKVMWVDATSIEQIANALRQLAPWSPQPDKAEQAAQSLLDQ
YAQLKAQYADKPKKRVFLQFGINPPFTSGKESIQNQVLEVCGGENIFKDSRVPWPQVSRE
QVLARSPQAIVITGGPDQIPKIKQYWGEQLKIPVIPLTSDWFERASPRIILAAQQLCNAL
SQVDLEHHHHHH

Ligands and cofactors

ID	Name	Formula	Copies
CNC	Cyanocobalamin	C63 H89 Co N14 O14 P	2

Primary citation

Crystal structures of the BtuF periplasmic-binding protein for vitamin B12 suggest a functionally important reduction in protein mobility upon ligand binding. Karpowich, N.K., Huang, H.H., Smith, P.C. et al. J Biol Chem (2003) 278:8429-8434. DOI 10.1074/jbc.M212239200 · PubMed

Other PDB entries of the same protein (UniProt P37028 (AlphaFold model), which also has an AlphaFold model), best resolution first:

5M29 1.5 Å, Structure of cobinamide-bound BtuF, the periplasmic vitamin B12 binding protein in E.coli
5M3B 1.5 Å, Structure of cobinamide-bound BtuF mutant W66L, the periplasmic vitamin B12 binding…
5M34 1.6 Å, Structure of cobinamide-bound BtuF mutant W66Y, the periplasmic vitamin B12 binding…
5M2Q 1.7 Å, Structure of cobinamide-bound BtuF mutant W66F, the periplasmic vitamin B12 binding…
1N2Z 2.0 Å, 2.0 Angstrom structure of BtuF, the vitamin B12 binding protein of E. coli
2QI9 2.6 Å, ABC-transporter BtuCD in complex with its periplasmic binding protein BtuF
5OVW 2.65 Å, Nanobody-bound BtuF, the vitamin B12 binding protein in Escherichia coli
1N4D 3.0 Å, The Ligand-Free Structure of E coli BtuF, the Periplasmic Binding Protein for Vitamin B12
4FI3 3.47 Å, Structure of vitamin B12 transporter BtuCD-F in a nucleotide-bound state
4DBL 3.49 Å, Crystal structure of E159Q mutant of BtuCDF

Browse structure collections

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