1EK4: Beta-ketoacyl [acyl carrier protein] synthase I

Beta-ketoacyl [acyl carrier protein] synthase I in complex with dodecanoic acid to 1.85 resolution. Determined by X-ray diffraction at 1.85 Å resolution. Released 11 Apr 2001.

Method: X-ray diffraction
Resolution: 1.85 Å
Organism: Escherichia coli
Chains: 4
Atoms: 12,770
Mol. weight: 177.1 kDa
Ligands: DAO
Released: 11 Apr 2001

Explore 1EK4 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

1EK4 contains 84 α-helices and 106 β-strands across 4 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: 20 helices, 28 β-strands

Element	Residues	Length	Sheet
β-strand	4-12	9	1
β-strand	13	1	2
β-strand	16	1	2
α-helix	19-28	10
β-strand	34-35	2	3
α-helix	37-42	6
β-strand	48-49	2	3
β-strand	50	1	4
α-helix	62-65	4
α-helix	70-86	17
α-helix	90-93	4
β-strand	99-104	6	1
α-helix	110-120	11
α-helix	126-129	4
α-helix	133-137	5
α-helix	141-147	7
β-strand	156-157	2	1
β-strand	158-160	3	5
β-strand	161	1	6
β-strand	163	1	6
α-helix	165-178	14
β-strand	184-191	8	1
α-helix	195-203	9
β-strand	207	1	7
α-helix	215-217	3
β-strand	223	1	8
β-strand	229	1	7
β-strand	231	1	9
β-strand	232	1	4
β-strand	234-242	9	1
α-helix	243-248	6
β-strand	255-264	10	1
α-helix	275-285	11
β-strand	294-296	3	1
α-helix	303-317	15
α-helix	321-322	2
β-strand	323-325	3	1
α-helix	328-331	4
β-strand	333	1	9
α-helix	335-337	3
α-helix	338-352	15
β-strand	354-355	2	10
β-strand	364	1	8
α-helix	366-368	3
β-strand	373	1	1
β-strand	378-379	2	10
β-strand	384-391	8	1
β-strand	395-402	8	1

Chain B: 23 helices, 26 β-strands

Element	Residues	Length	Sheet
β-strand	4-12	9	11
β-strand	13	1	12
β-strand	16	1	12
α-helix	19-28	10
β-strand	34-35	2	13
α-helix	37-42	6
β-strand	48-49	2	13
β-strand	50	1	14
α-helix	62-65	4
α-helix	70-86	17
α-helix	90-93	4
β-strand	99-104	6	11
α-helix	110-120	11
α-helix	126-129	4
α-helix	133-137	5
α-helix	141-147	7
β-strand	156-157	2	11
β-strand	158-160	3	5
α-helix	162-164	3
α-helix	165-178	14
β-strand	184-191	8	11
α-helix	195-203	9
β-strand	207	1	15
α-helix	215-217	3
β-strand	223	1	16
β-strand	229	1	15
β-strand	231	1	17
β-strand	232	1	14
β-strand	234-242	9	11
α-helix	243-248	6
α-helix	251-253	3
β-strand	255-264	10	11
α-helix	275-285	11
β-strand	294-296	3	11
α-helix	303-317	15
α-helix	321-322	2
β-strand	323-325	3	11
α-helix	328-331	4
β-strand	333	1	17
α-helix	335-337	3
α-helix	338-352	15
β-strand	354-355	2	18
β-strand	364	1	16
α-helix	366-368	3
β-strand	373	1	11
β-strand	378-379	2	18
β-strand	384-391	8	11
β-strand	395-402	8	11
α-helix	403-405	3

Chain C: 21 helices, 26 β-strands

Element	Residues	Length	Sheet
β-strand	4-12	9	19
β-strand	13	1	20
β-strand	16	1	20
α-helix	19-28	10
β-strand	34-35	2	21
α-helix	37-42	6
β-strand	48-49	2	21
β-strand	50	1	22
α-helix	62-65	4
α-helix	70-86	17
α-helix	90-93	4
β-strand	99-104	6	19
α-helix	110-120	11
α-helix	125-129	5
α-helix	133-137	5
α-helix	141-147	7
β-strand	156-157	2	19
β-strand	158-160	3	23
α-helix	162-164	3
α-helix	165-178	14
β-strand	184-191	8	19
α-helix	195-203	9
β-strand	207	1	24
α-helix	215-217	3
β-strand	223	1	25
β-strand	229	1	24
β-strand	231	1	26
β-strand	232	1	22
β-strand	234-242	9	19
α-helix	243-248	6
β-strand	255-264	10	19
α-helix	275-285	11
β-strand	294-296	3	19
α-helix	303-317	15
β-strand	323-325	3	19
α-helix	328-331	4
β-strand	333	1	26
α-helix	335-337	3
α-helix	338-352	15
β-strand	354-355	2	27
β-strand	364	1	25
α-helix	366-368	3
β-strand	373	1	19
β-strand	378-379	2	27
β-strand	384-391	8	19
β-strand	395-402	8	19
α-helix	403-405	3

Chain D: 20 helices, 26 β-strands

Element	Residues	Length	Sheet
β-strand	4-12	9	28
β-strand	13	1	29
β-strand	16	1	29
α-helix	19-28	10
β-strand	34-35	2	30
α-helix	37-42	6
β-strand	48-49	2	30
β-strand	50	1	31
α-helix	62-65	4
α-helix	70-86	17
α-helix	90-93	4
β-strand	99-104	6	28
α-helix	110-120	11
α-helix	126-129	4
α-helix	133-137	5
α-helix	141-147	7
β-strand	156-157	2	28
β-strand	158-160	3	23
α-helix	162-164	3
α-helix	165-178	14
β-strand	184-191	8	28
α-helix	195-202	8
β-strand	207	1	32
α-helix	215-218	4
β-strand	223	1	33
β-strand	229	1	32
β-strand	231	1	34
β-strand	232	1	31
β-strand	234-242	9	28
α-helix	243-248	6
β-strand	255-264	10	28
α-helix	275-285	11
β-strand	294-296	3	28
α-helix	303-317	15
β-strand	323-325	3	28
α-helix	328-331	4
β-strand	333	1	34
α-helix	335-337	3
α-helix	338-352	15
β-strand	354-355	2	35
β-strand	364	1	33
α-helix	366-368	3
β-strand	373	1	28
β-strand	378-379	2	35
β-strand	384-391	8	28
β-strand	395-402	8	28

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Beta-ketoacyl [acyl carrier protein] synthase I	A, B, C, D	protein	418	Escherichia coli	P0A953 (AlphaFold model)

Sequence of entity 1 (A, B, C, D), FASTA

>1EK4_1 BETA-KETOACYL [ACYL CARRIER PROTEIN] SYNTHASE I (chains A, B, C, D)
MRGSHHHHHHGSMKRVVITGLGIVSSIGNNQQEVLASLREGRSGITFSQELKDSGMRSHV
WGNVKLDTTGLIDRKVVRFMSDASIYAFLSMEQAIADAGLSPEAYQNNPRVGLIAGSGGG
SPRFQVFGADAMRGPRGLKAVGPYVVTKAMASGVSACLATPFKIHGVNYSISSASATSAH
CIGNAVEQIQLGKQDIVFAGGGEELCWEMACEFDAMGALSTKYNDTPEKASRTYDAHRDG
FVIAGGGGMVVVEELEHALARGAHIYAEIVGYGATSDGADMVAPSGEGAVRCMKMAMHGV
DTPIDYLNSHGTSTPVGDVKELAAIREVFGDKSPAISATKAMTGHSLGAAGVQEAIYSLL
MLEHGFIAPSINIEELDEQAAGLNIVTETTDRELTTVMSNSFGFGGTNATLVMRKLKD

Ligands and cofactors

ID	Name	Formula	Copies
DAO	Lauric acid	C12 H24 O2	4

Primary citation

Structures of beta-ketoacyl-acyl carrier protein synthase I complexed with fatty acids elucidate its catalytic machinery. Olsen, J.G., Kadziola, A., von Wettstein-Knowles, P. et al. Structure (2001) 9:233-243. DOI 10.1016/S0969-2126(01)00583-4 · PubMed

Other PDB entries of the same protein (UniProt P0A953 (AlphaFold model), which also has an AlphaFold model), best resolution first:

2VBA 1.36 Å, beta-ketoacyl-ACP synthase I (KAS) from E. coli with bound amino- thiazole inhibitor
2VB9 1.5 Å, beta-ketoacyl-ACP synthase I (KAS) from E. coli, apo structure
2VB8 1.52 Å, beta-ketoacyl-ACP synthase I (KAS) from E. coli with bound inhibitor thiolactomycin
6OKC 1.55 Å, Crosslinked Crystal Structure of Type II Fatty Acid Synthase Ketosynthase, FabB, and…
2VB7 1.6 Å, beta-ketoacyl-ACP synthase I (KAS) from E. coli, apo structure after soak in PEG solution
2BYW 1.7 Å, Structure of Escherichia coli beta-ketoacyl (acyl carrier protein) synthase I LYS328ALA…
7SQI 1.7 Å, Crosslinked Crystal Structure of Type II Fatty Acid Synthase Ketosynthase, FabB, and…
2BZ4 1.86 Å, structure of E.coli KAS I H298Q mutant
2BUH 1.9 Å, E. Coli beta-ketoacyl (acyl carrier protein) synthase I, 120 K
8SMS 1.93 Å, Crosslinked Crystal Structure of Type II Fatty Acid Synthase, FabB, and cerulenin…
2BYZ 1.95 Å, Structure of E.coli KAS I H298Q mutant in complex with C12 fatty acid
1H4F 2.0 Å, E. Coli beta-ketoacyl [acyl carrier protein] synthase I K328R

Browse structure collections

About this viewer

MolViewer shows 1EK4 directly in your browser with nothing to install. Switch between cartoon, ball-and-stick, spacefill and surface views, color by chain, secondary structure or B-factor, measure distances, angles and dihedrals, and share or embed the view.