X-ray diffraction
1.85Å resolution

X-ray structure of MHV PLP2 (Cys1716Ser) catalytic mutant in complex with free ubiquitin

Entry authors: Mesecar AD, Chen Y

Function and Biology Details

Reactions catalysed:
Nucleoside triphosphate + RNA(n) = diphosphate + RNA(n+1)
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.
ATP + H(2)O = ADP + phosphate
Biochemical function:
Biological process:
Cellular component:
  • not assigned

Structure analysis Details

Assembly composition:
hetero dimer (preferred)
Entry contents:
2 distinct polypeptide molecules
Macromolecules (2 distinct):
Papain-like proteinase Chains: A, B
Molecule details ›
Chains: A, B
Length: 303 amino acids
Theoretical weight: 33.89 KDa
Source organism: Murine hepatitis virus strain A59
Expression system: Escherichia coli
  • Canonical: P0C6X9 (Residues: 1609-1911; Coverage: 4%)
Gene names: 1a-1b, rep
Ubiquitin Chains: C, D
Molecule details ›
Chains: C, D
Length: 76 amino acids
Theoretical weight: 8.58 KDa
Source organism: Homo sapiens
Expression system: Escherichia coli K-12
  • Canonical: P0CG47 (Residues: 153-228; Coverage: 33%)
Gene name: UBB
Sequence domains: Ubiquitin family

Ligands and Environments

3 bound ligands:

No modified residues

Experiments and Validation Details

Entry percentile scores
X-ray source: APS BEAMLINE 21-ID-G
Spacegroup: C2
Unit cell:
a: 199.515Å b: 43.388Å c: 110.159Å
α: 90° β: 114.85° γ: 90°
R R work R free
0.158 0.157 0.197
Expression systems:
  • Escherichia coli
  • Escherichia coli K-12