1W8N: Contribution of the Active Site Aspartic Acid to Catalysis in the Bacterial Neuraminidase From Micromonospora Viridifaciens

A recombinant D92G mutant sialidase from Micromonospora viridifaciens has been cloned, expressed and purified. Kinetic studies reveal that the replacement of the conserved aspartic acid with glycine results in a catalytically competent retaining sialidase that possesses significant activity against activated substrates. The contribution of this aspartate residue to the free energy of hydrolysis for natural substrates is greater than 19 kJ/mol. The three dimensional structure of the D92G mutant shows that the removal of aspartic acid 92 causes no significant re-arrangement of the active site, and that an ordered water molecule substitutes for the carboxylate group of D92.
PDB ID: 1W8NDownload
MMDB ID: 29737
PDB Deposition Date: 2004/9/24
Updated in MMDB: 2004/11
Experimental Method:
x-ray diffraction
Resolution: 2.1  Å
Source Organism:
Similar Structures:
Biological Unit for 1W8N: monomeric; determined by author and by software (PQS)
Molecular Components in 1W8N
Label Count Molecule
Protein (1 molecule)
Bacterial Sialidase
Molecule annotation
Chemicals (3 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB