6xb2

X-ray diffraction
2.1Å resolution

Room temperature X-ray crystallography reveals catalytic cysteine in the SARS-CoV-2 3CL Mpro is highly reactive: Insights for enzyme mechanism and drug design

Released:

Function and Biology Details

Reactions catalysed:
S-adenosyl-L-methionine + a 5'-(5'-triphosphoguanosine)-[mRNA] = S-adenosyl-L-homocysteine + a 5'-(N(7)-methyl 5'-triphosphoguanosine)-[mRNA]
S-adenosyl-L-methionine + a 5'-(N(7)-methyl 5'-triphosphoguanosine)-(ribonucleotide)-[mRNA] = S-adenosyl-L-homocysteine + a 5'-(N(7)-methyl 5'-triphosphoguanosine)-(2'-O-methyl-ribonucleotide)-[mRNA]
Nucleoside triphosphate + RNA(n) = diphosphate + RNA(n+1)
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.
ATP + H(2)O = ADP + phosphate
Biochemical function:
Biological process:
Cellular component:
  • not assigned

Structure analysis Details

Assembly composition:
homo dimer (preferred)
PDBe Complex ID:
PDB-CPX-145080 (preferred)
Entry contents:
1 distinct polypeptide molecule
Macromolecule:
3C-like proteinase nsp5 Chain: A
Molecule details ›
Chain: A
Length: 306 amino acids
Theoretical weight: 33.83 KDa
Source organism: Severe acute respiratory syndrome coronavirus 2
Expression system: Escherichia coli
UniProt:
  • Canonical: P0DTD1 (Residues: 3264-3569; Coverage: 4%)
Gene names: 1a-1b, rep
Sequence domains: Coronavirus endopeptidase C30

Ligands and Environments

2 bound ligands:
No modified residues

Experiments and Validation Details

Entry percentile scores
X-ray source: RIGAKU MICROMAX-007
Unit cell:
a: 45.292Å b: 54.636Å c: 115.157Å
α: 90° β: 100.739° γ: 90°
R-values:
R R work R free
0.198 0.196 0.257
Expression system: Escherichia coli