Family M85
Summary for family M85
| Family type peptidase | M85.001 - NleC peptidase (Escherichia coli) (Escherichia coli), MEROPS Accession MER0195406 (peptidase unit: 21-285) |
| Content of family | Peptidase family M85 contains endopeptidases. |
| History |
Identifier created: MEROPS 9.4 (31 January 2011)
Pathogenic bacteria can manipulate host cells by affecting cell signalling pathways. Enteropathogenic and enterohemorrhagic Escherichia coli inject virulence factors into host cell by means of a needle-like protein complex called the type three secretion system. The proteins NleC and NleE, injected in this way, are two factors that down-regulate the NFkappaB signalling pathway. NleC has been shown to be a metallopeptidase that cleaves the p65 subunit of NF-kappaB, disrupting activation and inhibiting the inflammation response in the host (Yen et al., 2010). |
| Catalytic type | Metallo |
| Active site residues | H183 E184 H187 D194 Y227 |
| Active site | There is a conserved HEXXH motif, which in metallopeptidase from clan MA has been shown to be metal-binding. The histidines are zinc ligands and the glutamate an active site residue. In NleC, site-directed mutagenesis of the second histidine prevented cleavage of p65 (Yen et al., 2010). |
| Activities and specificities | The p65 subunit of NF-kappaB is cleaved, but cleavage positions have not been identified. |
| Inhibitors | EDTA (10 mM) prevented cleavage of p65 (Yen et al., 2010). |
| Molecular structure | No tertiary structure has been solved and family M85 is included in clan MA because of the presence of the HEXXH metal-binding motif. |
| Clan | MA |
| Subclan | MA(E) |
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Distribution of family
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Bacteria |
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Archaea |
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Protozoa |
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Fungi |
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Plants |
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Animals |
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Viruses |
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| Peptidases and Homologues |
MEROPS ID |
Structure |
| NleC peptidase (Escherichia coli) | M85.001 | Yes |
| Family M85 unassigned peptidases | unassigned | - |
