Table 1.

Summary of selected PAMPs^* recognized by plants (adapted from Nürnberger and Lipka, Schwessinger and Zipfel)⁶,⁷

PAMP	Plant	Pathogen(s)	Active epitope
β-glucans	Rice Legume	Fungi (Pyricularia oryzae), Oomycetes (Phytophthora spp.,), Brown algae	Tetraglucosyl glucitol, branced hepta-β-glucoside, linear oligo-β-glucosides
Cerebrosides A, C	Rice	Fungi (Magnaporthe spp.,)	Sphingoid base
Chitin/Chitosan	Arabidopsis, rice, tomato and wheat	All fungi	Chitin oligosaccharides (degree of polymerization >3)
Cold shock protein	Solanaceae	Gram-negative bacteria, Gram-positive bacteria	RNP-1 motif (amino terminal fragment of cold shock protein)
Elongation factor (EF-Tu)	Brassicaceae	Gram-negative bacteria	elf18 (N-acetylated amino terminal fragment of EF-Tu)
Ergosterol	Tomato	All fungi
Flagellin	Most plants (except rice)	Gram-negative bacteria	flg22 (amino terminal fragment of flagellin)
Harpin (HrpZ)	Various plants	Gram-negative bacteria (Pseudomonads, Erwinia)	Undefined
Invertase	Tomato	Yeast	N-mannosylated peptide (fragment of the peptide)
Lipid-transfer proteins (elicitins)	Tobacco	Oomycetes (Phytophthora spp., Pythium spp.,)	Undefined
LPS	Arabidopsis, pepper and tobacco	Gram-negative bacteria (Xanthomonads, Pseudomonads, Burkholderia spp.)	Lipid A/inner core/Glucosamine backbone/Combinations of motifs?
Necrosis-inducing protein	Many dicot plants	Bacteria (Bacillus spp.,), Fungi (Fusarium spp., Verticillium spp.,) Oomycetes (Phytophthora spp., Pythium spp.)	Undefined
Peptidoglycan	Arabidopsis and tobacco	Gram-positive bacteria	Muramyl dipeptide
Rhamnolipids**	Grapevine	Pseudomonas species	Mono-/dirhamnolipids
Siderophores***	Tobacco	Undefined	Pseudomonas fluorenscens
Sulphated fucans	Tobacco	Brown algae	Fucan oligosaccharide
Transglutaminase	Parsley and potato	Oomycetes (Phytophthora spp.)	Pep-13 motif (surface-exposed epitope of the transglutaminase)
Xylanase	Tobacco and tomato	Fungi (Trichoderma spp.)	TKLGE pentapeptide (suface-exposed epitope of xylanase)

^*PAMPs may be described as invariant epitopes within molecules that are fundamental to the pathogens' fitness; They are widely distributed among different microbes, absent from the host and recognized by a wide array of potential hosts

^**varnier et al.;⁸

^***van Loon et al.⁹