4K1E: Kallikrein-4

Atomic resolution crystal structures of Kallikrein-Related Peptidase 4 complexed with a modified SFTI inhibitor FCQR. Determined by X-ray diffraction at 1.3 Å resolution. Released 9 Apr 2014.

Method: X-ray diffraction
Resolution: 1.3 Å
Organisms: Homo sapiens, Helianthus annuus
Chains: 2
Atoms: 1,922
Mol. weight: 25.63 kDa
Ligands: LI
Released: 9 Apr 2014

Explore 4K1E in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

4K1E contains 8 α-helices and 21 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: 8 helices, 19 β-strands

Element	Residues	Length	Sheet
β-strand	17	1	1
β-strand	20-21	2	2
α-helix	22-23	2
β-strand	30-35	6	3
β-strand	38-48	10	3
β-strand	51-54	4	3
α-helix	56-58	3
β-strand	63-67	5	3
β-strand	72	1	4
β-strand	81-85	5	3
β-strand	87-90	4	3
β-strand	104-107	4	3
α-helix	122	1
β-strand	123	1	2
α-helix	124	1
β-strand	135-140	6	2
α-helix	150-152	3
β-strand	154	1	4
β-strand	156-162	7	2
α-helix	165-171	7
β-strand	180-184	5	2
β-strand	189	1	1
β-strand	198-201	4	2
β-strand	208-217	10	2
β-strand	225-230	6	2
α-helix	231-233	3
α-helix	235-243	9

Chain B: 0 helices, 2 β-strands

Element	Residues	Length	Sheet
β-strand	2-4	3	2
β-strand	10-11	2	2

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Kallikrein-4	A	protein	223	Homo sapiens	Q9Y5K2 (AlphaFold model)
Trypsin inhibitor 1	B	protein	14	Helianthus annuus	Q4GWU5 (AlphaFold model)

Sequence of entity 1 (A), FASTA

>4K1E_1 Kallikrein-4 (chains A)
IINGEDCSPHSQPWQAALVMENELFCSGVLVHPQWVLSAAHCFQNSYTIGLGLHSLEADQ
EPGSQMVEASLSVRHPEYNRPLLANDLMLIKLDESVSESDTIRSISIASQCPTAGNSCLV
SGWGLLANGRMPTVLQCVNVSVVSEEVCSKLYDPLYHPSMFCAGGGQDQKDSCNGDSGGP
LICNGYLQGLVSFGKAPCGQVGVPGVYTNLCKFTEWIEKTVQA

Sequence of entity 2 (B), FASTA

>4K1E_2 Trypsin inhibitor 1 (chains B)
GFCQRSIPPICFPD

Ligands and cofactors

ID	Name	Formula	Copies
LI	Lithium ion	Li	1

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

Primary citation

Direct and indirect mechanisms of KLK4 inhibition revealed by structure and dynamics. Riley, B.T., Ilyichova, O., Costa, M.G.S. et al. Sci Rep (2016) 6:35385-35385. DOI 10.1038/srep35385 · PubMed

Other PDB entries of the same protein (UniProt Q9Y5K2 (AlphaFold model), which also has an AlphaFold model), best resolution first:

4K8Y 1.0 Å, Atomic resolution crystal structures of Kallikrein-Related Peptidase 4 complexed with…
4KEL 1.15 Å, Atomic resolution crystal structure of Kallikrein-Related Peptidase 4 complexed with a…
6O21 1.15 Å, Crystal Structure of Human KLK4 in Complex With Cleaved SFTI-FCQR(Asn14)[1,14] Inhibitor
7JOD 1.33 Å, Crystal structure of BbKI complexed with Human Kallikrein 4
7JQK 1.33 Å, Crystal structure of the R64A mutant of Bauhinia Bauhinioides Kallikrein Inhibitor…
7JQN 1.5 Å, Crystal structure of the R64M mutant of Bauhinia Bauhinioides Kallikrein Inhibitor…
7JQO 1.6 Å, Crystal structure of the R64D mutant of Bauhinia Bauhinioides Kallikrein Inhibitor…
6NVB 1.64 Å, Crystal structure of the inhibitor-free form of the serine protease kallikrein-4
7JOW 1.91 Å, Crystal structure of BbKI complexed with Human Kallikrein 4
2BDG 1.95 Å, Human Kallikrein 4 complex with nickel and p-aminobenzamidine
6KBR 2.0 Å, Crystal structure of Human KLK4 and SPINK2 derived KLK4 inhibitor complex
7JOS 2.1 Å, Crystal structure of BbKI complexed with Human Kallikrein 4

Browse structure collections

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