Family I83
Summary for family I83
| Family type peptidase | I83.001 - AmFPI-1 (Antheraea sp.) (Antheraea mylitta), MEROPS Accession MER0149910 (inhibitor unit: 20-105) |
| Content of family | Family I83 contains inhibitors of serine endopeptidases. |
| History |
Identifier created: MEROPS 8.5 (24 August 2009)
Insect defence mechanisms against pathogenic attack include the secretion of peptidase inhibitors into the hemolymph. Caterpillars of the moth Antheraea mylitta, which are economically important because they produce Indian tasar silk, secrete the inhibitor AmFPI-1 (I83.001; Roy et al., 2009). |
| Peptidases inhibited | AmFPI-1 inhibits oryzin (S08.053) from Aspergillus oryzae but not trypsin (S01.151; Roy et al., 2009). The inducible serine protease inhibitor 1 (I83.002) from the wax moth (Galleria mellonella) inhibits vertebrate and fungal trypsins (S01.103; Frobius et al., 2000). |
| Mechanism of inhibition | Because the reactive site loop of AmFPI-1 can be superimposed on those of other serine peptidase inhibitors, inhibition is believed to be by the Laskowski mechanism also termed the 'standard' mechanism (Laskowski & Kato, 1980). |
| Molecular structure | The tertiary structure of AmFPI-1 has been solved, and shows a unique fold consisting of three helices and five beta strands which are stabilized by six disulfide bonds (Roy et al., 2009). Family I83 is therefore the founder member of clan JH. |
| Clan | JH |
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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 |
details |
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Animals |
details |
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Viruses |
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| Inhibitors and Homologues |
MEROPS ID |
Structure |
| AmFPI-1 (Antheraea sp.) | I83.001 | Yes |
| inducible serine protease inhibitor 1 (Galleria mellonella) | I83.002 | - |
| Family I83 non-peptidase homologues | non-peptidase homologue | - |
| Family I83 unassigned peptidases | unassigned | - |
