9BOS: Trypsin-3

Human mesotrypsin (PRSS3) unliganded and in an active (E) conformation. Determined by X-ray diffraction at 1.7 Å resolution. Released 11 Jun 2025.

Method: X-ray diffraction
Resolution: 1.7 Å
Organism: Homo sapiens
Chains: 1
Atoms: 1,865
Mol. weight: 24.46 kDa
Ligands: 2F2, CA
Released: 11 Jun 2025

Explore 9BOS in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9BOS contains 9 α-helices and 20 β-strands across 1 chain. 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: 9 helices, 20 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	40-48	9	3
β-strand	51-54	4	3
α-helix	56-58	3
β-strand	64-67	4	3
β-strand	72	1	4
β-strand	81-90	10	3
β-strand	104-108	5	3
α-helix	111-114	4
β-strand	122	1	2
α-helix	123-124	2
α-helix	128-130	3
β-strand	135-140	6	2
β-strand	154	1	4
β-strand	156-162	7	2
α-helix	163-164	2
α-helix	165-171	7
β-strand	180-183	4	2
β-strand	189	1	1
β-strand	198-201	4	2
β-strand	204-215	8	2
β-strand	221A	1	5
β-strand	224	1	5
β-strand	226-230	5	2
α-helix	231-234	4
α-helix	235-244	10

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Trypsin-3	A	protein	224	Homo sapiens	P35030 (AlphaFold model)

Sequence of entity 1 (A), FASTA

>9BOS_1 Trypsin-3 (chains A)
IVGGYTCEENSLPYQVSLNSGSHFCGGSLISEQWVVSAAHCYKTRIQVRLGEHNIKVLEG
NEQFINAAKIIRHPKYNRDTLDNDIMLIKLSSPAVINARVSTISLPTTPPAAGTECLISG
WGNTLSFGADYPDELKCLDAPVLTQAECKASYPGKITNSMFCVGFLEGGKDSCQRDAGGP
VVCNGQLQGVVSWGHGCAWKNRPGVYTKVYNYVDWIKDTIAANS

Ligands and cofactors

ID	Name	Formula	Copies
2F2	dimethyl ether	C2 H6 O	2
CA	Calcium ion	Ca	1

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

Primary citation

Discovery of an autoinhibited conformation in mesotrypsin reveals a strategy for selective serine protease inhibition. Coban, M., Gokara, M., Forero Vargas, L.M. et al. Sci Adv (2025) 11:eadu9129-eadu9129. DOI 10.1126/sciadv.adu9129 · PubMed

Other PDB entries of the same protein (UniProt P35030 (AlphaFold model), which also has an AlphaFold model), best resolution first:

5TP0 1.25 Å, Human mesotrypsin in complex with diminazene
3P95 1.3 Å, Human mesotrypsin complexed with bovine pancreatic trypsin inhibitor variant…
2R9P 1.4 Å, Human mesotrypsin complexed with bovine pancreatic trypsin inhibitor(BPTI)
4DG4 1.4 Å, Human mesotrypsin-S39Y complexed with bovine pancreatic trypsin inhibitor (BPTI)
5JBT 1.4 Å, Mesotrypsin in complex with cleaved amyloid precursor like protein 2 inhibitor (APLP2)
3P92 1.6 Å, Human mesotrypsin complexed with bovine pancreatic trypsin inhibitor variant…
9BOT 1.6 Å, Human mesotrypsin (PRSS3) unliganded and in autoinhibited (E*) conformation
4U32 1.65 Å, Human mesotrypsin complexed with HAI-2 Kunitz domain 1
1H4W 1.7 Å, Structure of human trypsin IV (brain trypsin)
5C67 1.83 Å, Human Mesotrypsin in complex with amyloid precursor protein inhibitor variant…
6BX8 1.98 Å, Human Mesotrypsin (PRSS3) Complexed with Tissue Factor Pathway Inhibitor Variant…
6GFI 2.3 Å, Structure of Human Mesotrypsin in complex with APPI variant T11V/M17R/I18F/F34V

Browse structure collections

About this viewer

MolViewer shows 9BOS 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.