4CHA: Alpha-*chymotrypsin

Structure of alpha-*chymotrypsin refined at 1.68 Å resolution. Determined by X-ray diffraction at 1.68 Å resolution. Released 1 Apr 1985.

Method: X-ray diffraction
Resolution: 1.68 Å
Organism: Bos taurus
Chains: 6
Atoms: 3,591
Mol. weight: 50.53 kDa
Released: 1 Apr 1985

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

Secondary structure: helices and β-sheets

4CHA contains 15 α-helices and 38 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 B: 4 helices, 13 β-strands

Element	Residues	Length	Sheet
β-strand	17	1	1
β-strand	20-21	2	2
α-helix	22-23	2
β-strand	30-34	5	3
β-strand	40-46	7	3
β-strand	51-54	4	3
α-helix	56-58	3
β-strand	65-68	4	3
β-strand	72	1	4
β-strand	81-90	10	3
β-strand	95	1	5
β-strand	100	1	5
β-strand	104-108	5	3
α-helix	111-114	4
α-helix	120-121	2
β-strand	122	1	2
β-strand	135-140	6	2

Chain C: 4 helices, 7 β-strands

Element	Residues	Length	Sheet
β-strand	154	1	4
β-strand	156-162	7	2
α-helix	165-172	8
α-helix	173-175	3
β-strand	180-184	5	2
β-strand	189	1	1
β-strand	198-203	6	2
β-strand	206-215	10	2
β-strand	225-230	6	2
α-helix	231-233	3
α-helix	235-244	10

Chain F: 4 helices, 11 β-strands

Element	Residues	Length	Sheet
β-strand	17	1	6
β-strand	20-21	2	7
α-helix	22-23	2
β-strand	30-34	5	8
β-strand	40-46	7	8
β-strand	51-54	4	8
α-helix	56-58	3
β-strand	65-68	4	8
β-strand	72	1	9
β-strand	81-90	10	8
β-strand	104-108	5	8
α-helix	111-114	4
α-helix	120-121	2
β-strand	122	1	7
β-strand	135-140	6	7

Chain G: 3 helices, 7 β-strands

Element	Residues	Length	Sheet
β-strand	154	1	9
β-strand	156-162	7	7
α-helix	165-172	8
α-helix	173-175	3
β-strand	180-184	5	7
β-strand	189	1	6
β-strand	198-203	6	7
β-strand	206-215	10	7
β-strand	225-230	6	7
α-helix	231-244	14

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Alpha-chymotrypsin a	A, E	protein	13	Bos taurus	P00766 (AlphaFold model)
Alpha-chymotrypsin a	B, F	protein	131	Bos taurus	P00766 (AlphaFold model)
Alpha-chymotrypsin a	C, G	protein	97	Bos taurus	P00766 (AlphaFold model)

Sequence of entity 1 (A, E), FASTA

>4CHA_1 ALPHA-CHYMOTRYPSIN A (chains A, E)
CGVPAIQPVLSGL

Sequence of entity 2 (B, F), FASTA

>4CHA_2 ALPHA-CHYMOTRYPSIN A (chains B, F)
IVNGEEAVPGSWPWQVSLQDKTGFHFCGGSLINENWVVTAAHCGVTTSDVVVAGEFDQGS
SSEKIQKLKIAKVFKNSKYNSLTINNDITLLKLSTAASFSQTVSAVCLPSASDDFAAGTT
CVTTGWGLTRY

Sequence of entity 3 (C, G), FASTA

>4CHA_3 ALPHA-CHYMOTRYPSIN A (chains C, G)
ANTPDRLQQASLPLLSNTNCKKYWGTKIKDAMICAGASGVSSCMGDSGGPLVCKKNGAWT
LVGIVSWGSSTCSTSTPGVYARVTALVNWVQQTLAAN

Primary citation

Structure of alpha-chymotrypsin refined at 1.68 A resolution. Tsukada, H., Blow, D.M. J Mol Biol (1985) 184:703-711. DOI 10.1016/0022-2836(85)90314-6 · PubMed

Other PDB entries of the same protein (UniProt P00766 (AlphaFold model), which also has an AlphaFold model), best resolution first:

5R43 1.0 Å, Crystal Structure of deuterated gamma-Chymotrypsin at pH 7.5, cryo temperature
5R42 1.05 Å, Crystal Structure of deuterated gamma-Chymotrypsin at pH 7.5, room temperature
5R44 1.05 Å, Crystal Structure of gamma-Chymotrypsin at pH 7.5, room temperature
5R45 1.05 Å, Crystal Structure of gamma-Chymotrypsin at pH 7.5, cryo temperature
5R46 1.05 Å, Crystal Structure of deuterated gamma-Chymotrypsin at pH 5.6, room temperature
5R48 1.05 Å, Crystal Structure of gamma-Chymotrypsin at pH 5.6, room temperature
5R49 1.05 Å, Crystal Structure of gamma-Chymotrypsin at pH 5.6, cryo temperature
5R4B 1.05 Å, Crystal Structure of deuterated gamma-Chymotrypsin at pH 9, cryo temperature
5R4D 1.05 Å, Crystal Structure of gamma-Chymotrypsin at pH 9, cryo temperature
5R47 1.1 Å, Crystal Structure of deuterated gamma-Chymotrypsin at pH 5.6, cryo temperature
5R4C 1.15 Å, Crystal Structure of gamma-Chymotrypsin at pH 9, room temperature
5R4A 1.2 Å, Crystal Structure of deuterated gamma-Chymotrypsin at pH 9, room temperature

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