| Elicitin | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 beta-cinnamomin in complex with ergosterol | |||||||||
| Identifiers | |||||||||
| Symbol | Elicitin | ||||||||
| Pfam | PF00964 | ||||||||
| InterPro | IPR002200 | ||||||||
| SCOP2 | 1beo / SCOPe / SUPFAM | ||||||||
| |||||||||
In molecular biology, elicitins are a family of small, highly conserved proteins secreted by phytopathogenic microorganisms belonging to the Phytophthora and Pythium species. They are toxic proteins responsible for inducing a necrotic and systemic hypersensitive response in plants from the Solanaceae and Cruciferae families. Leaf necrosis provides immediate control of fungal invasion and induces systemic acquired resistance; both responses mediate basic protection against subsequent pathogen inoculation.
Members of this family share a high level of sequence similarity, but they differ in net charge, dividing them into two classes: alpha and beta. Alpha-elicitins are highly acidic, with a valine residue at position 13, whereas beta-elicitins are basic, with a lysine at the same position. Residue 13 is known to be involved in the control of necrosis and, being exposed, is thought to be involved in ligand/receptor binding. Phenotypically, the two classes can be distinguished by their necrotic properties: beta-elicitins are 100-fold more toxic and provide better subsequent protection.
References
- ^ Yu LM (May 1995). "Elicitins from Phytophthora and basic resistance in tobacco". Proc. Natl. Acad. Sci. U.S.A. 92 (10): 4088–94. Bibcode:1995PNAS...92.4088Y. doi:10.1073/pnas.92.10.4088. PMC 41891. PMID 7753775.
- Fefeu S, Bouaziz S, Huet JC, Pernollet JC, Guittet E (November 1997). "Three-dimensional solution structure of beta cryptogein, a beta elicitin secreted by a phytopathogenic fungus Phytophthora cryptogea". Protein Sci. 6 (11): 2279–84. doi:10.1002/pro.5560061101. PMC 2143581. PMID 9385630.