|Family type peptidase||M91.001 - NleD peptidase (Escherichia coli-type) (Escherichia coli), MEROPS Accession MER0331730 (peptidase unit: 1-232)|
|Content of family||Family M91 contains endopeptidases.|
Identifier created: MEROPS 9.7 (1 August 2012)|
NleD protein (M91.001) from enteropathogenic strains of Escherichia coli is a virulence factor that helps inactivate the inflammatory response by cleavage of host mitogen-activated protein kinase 9 (Baruch et al., 2011).
|Active site residues||E143 |
|Active site||NleD is assumed to be a zinc metallopeptidase because of the presence of an HEXXH motif, characteristic of peptidases in clan MA. Mutagenesis studies have confirmed that the glutamic acid within this motif is essential for activity (Baruch et al., 2011), and it is assumed to be a catalytic residue. The histidines in the HEXXH motif are assumed to be metal ligands, but the third metal ligand is unknown.|
|Inhibitors||The metal chelator 1,10-phenanthroline is inhibitory (Baruch et al., 2011).|
|Molecular structure||No tertiary structure has been solved for any member of the family. The family is included in clan MA because of the presence of the zinc-binding motif, HEXXH, and because NleD is not a membrane protein.|