3d23

X-ray diffraction
2.5Å resolution

Main protease of HCoV-HKU1

Released:

Function and Biology Details

Reactions catalysed:
GTP + a 5'-diphospho-[mRNA] = diphosphate + a 5'-(5'-triphosphoguanosine)-[mRNA]
Thiol-dependent hydrolysis of ester, thioester, amide, peptide and isopeptide bonds formed by the C-terminal Gly of ubiquitin (a 76-residue protein attached to proteins as an intracellular targeting signal).
TSAVLQ-|-SGFRK-NH(2) and SGVTFQ-|-GKFKK the two peptides corresponding to the two self-cleavage sites of the SARS 3C-like proteinase are the two most reactive peptide substrates. The enzyme exhibits a strong preference for substrates containing Gln at P1 position and Leu at P2 position.
Biochemical function:
Biological process:
Cellular component:
  • not assigned

Structure analysis Details

Assemblies composition:
hetero octamer
hetero tetramer (preferred)
PDBe Complex ID:
PDB-CPX-143065 (preferred)
Entry contents:
2 distinct polypeptide molecules
Macromolecules (2 distinct):
3C-like proteinase nsp5 Chains: A, B, C, D
Molecule details ›
Chains: A, B, C, D
Length: 302 amino acids
Theoretical weight: 33.01 KDa
Source organism: Human coronavirus HKU1 (isolate N1)
Expression system: Escherichia coli
UniProt:
  • Canonical: P0C6U3 (Residues: 3335-3634; Coverage: 7%)
Gene name: 1a
Sequence domains: Coronavirus endopeptidase C30
Structure domains:
N-[(5-METHYLISOXAZOL-3-YL)CARBONYL]ALANYL-L-VALYL-N~1~-((1R,2Z)-4-(BENZYLOXY)-4-OXO-1-{[(3R)-2-OXOPYRROLIDIN-3-YL]METHYL}BUT-2-ENYL)-L-LEUCINAMIDE Chains: E, F, G, H
Molecule details ›
Chains: E, F, G, H
Length: 6 amino acids
Theoretical weight: 681 Da
Source organism: synthetic construct
Expression system: Not provided

Ligands and Environments

No bound ligands
No modified residues

Experiments and Validation Details

Entry percentile scores
X-ray source: PHOTON FACTORY BEAMLINE BL-5A
Spacegroup: P41
Unit cell:
a: 91.77Å b: 91.77Å c: 187.914Å
α: 90° β: 90° γ: 90°
R-values:
R R work R free
0.232 0.229 0.285
Expression systems:
  • Escherichia coli
  • Not provided