1SLU: Ecotin

Rat anionic N143H, E151H trypsin complexed to A86H ecotin. Determined by X-ray diffraction at 1.8 Å resolution. Released 11 Jul 1996.

Method: X-ray diffraction
Resolution: 1.8 Å
Organisms: Escherichia coli, Rattus norvegicus
Chains: 2
Atoms: 2,804
Mol. weight: 40.13 kDa
Ligands: CA
Released: 11 Jul 1996

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

Secondary structure: helices and β-sheets

1SLU contains 13 α-helices and 30 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: 4 helices, 12 β-strands

Element	Residues	Length	Sheet
α-helix	14-16	3
β-strand	20-25	6	1
α-helix	27-29	3
α-helix	33-35	3
β-strand	36-48	13	2
β-strand	53-54	2	3
β-strand	55	1	4
β-strand	58-64	7	1
β-strand	69-75	7	1
β-strand	81-83	3	3
β-strand	93-98	6	2
β-strand	99	1	4
α-helix	102-105	4
β-strand	106-108	3	2
β-strand	115-120	6	1
β-strand	124-131	8	2

Chain B: 9 helices, 18 β-strands

Element	Residues	Length	Sheet
β-strand	17	1	5
β-strand	20-21	2	3
α-helix	22-23	2
β-strand	30-34	5	6
β-strand	40-48	9	6
β-strand	51-54	4	6
α-helix	56-58	3
β-strand	64-66	3	6
β-strand	72	1	7
β-strand	82-90	9	6
β-strand	104-108	5	6
β-strand	122	1	3
α-helix	123-124	2
α-helix	128-130	3
β-strand	135-140	6	3
β-strand	154	1	7
α-helix	155	1
β-strand	156-162	7	3
α-helix	163-164	2
α-helix	165-171	7
β-strand	180-183	4	3
β-strand	189	1	5
β-strand	198-201	4	3
β-strand	204-216	9	3
β-strand	226-229	4	3
α-helix	231-233	3
α-helix	235-243	9

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Ecotin	A	protein	142	Escherichia coli	P23827 (AlphaFold model)
Anionic trypsin	B	protein	223	Rattus norvegicus	P00763 (AlphaFold model)

Sequence of entity 1 (A), FASTA

>1SLU_1 ECOTIN (chains A)
AESVQPLEKIAPYPQAEKGMKRQVIQLTPQEDESTLKVELLIGQTLEVDCNLHRLGGKLE
NKTLEGWGYDYYVFDKVSSPVSTMMHCPDGKKEKKFVTAYLGDAGMLRYNSKLPIVVYTP
DNVDVKYRVWKAEEKIDNAVVR

Sequence of entity 2 (B), FASTA

>1SLU_2 ANIONIC TRYPSIN (chains B)
IVGGYTCQENSVPYQVSLNSGYHFCGGSLINDQWVVSAAHCYKSRIQVRLGEHNINVLEG
NEQFVNAAKIIKHPNFDRKTLNNDIMLIKLSSPVKLNARVATVALPSSCAPAGTQCLISG
WGHTLSSGVNHPDLLQCLDAPLLPQADCEASYPGKITDNMVCVGFLEGGKDSCQGDSGGP
VVCNGELQGIVSWGYGCALPDNPGVYTKVCNYVDWIQDTIAAN

Ligands and cofactors

ID	Name	Formula	Copies
CA	Calcium ion	Ca	1

Water and common crystallization additives (ACT) are not listed.

Primary citation

X-ray structures of a designed binding site in trypsin show metal-dependent geometry. Brinen, L.S., Willett, W.S., Craik, C.S. et al. Biochemistry (1996) 35:5999-6009. DOI 10.1021/bi9530200 · PubMed

Other PDB entries of the same protein (UniProt P23827 (AlphaFold model), which also has an AlphaFold model), best resolution first:

1IFG 2.0 Å, Crystal structure of a monomeric form of general protease inhibitor, ecotin in absence…
1N8O 2.0 Å, Crystal structure of a complex between bovine chymotrypsin and ecotin
1SLW 2.0 Å, Rat anionic N143H, E151H trypsin complexed to A86H ecotin; nickel-bound
1ECY 2.19 Å, Protease inhibitor ecotin
1FI8 2.2 Å, Rat granzyme B [N66Q] complexed to ecotin [81-84 iepd]
1SLX 2.2 Å, Rat anionic N143H, E151H trypsin complexed to A86H ecotin; zinc-bound
1XX9 2.2 Å, Crystal Structure of the FXIa Catalytic Domain in Complex with EcotinM84R
1AZZ 2.3 Å, Fiddler crab collagenase complexed to ecotin
1EZS 2.3 Å, Crystal structure of ecotin mutant M84R, W67A, G68A, Y69A, D70A bound to rat anionic…
1SLV 2.3 Å, Rat anionic N143H, E151H trypsin complexed to A86H ecotin; copper-bound
1EZU 2.4 Å, Ecotin Y69F, D70P bound to D102N trypsin
7PQN 2.4 Å, Catalytic fragment of MASP-2 in complex with ecotin

Browse structure collections

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