Pathogen-associated molecular pattern

Pathogen-associated molecular patterns, or PAMPs, are small molecular motifs consistently found on pathogens. They are recognized by toll-like receptors and other pattern recognition receptors (PRRs) in plants and animals.

They activate innate immune responses by identifying non-self molecules, protecting the plant from infection. Bacterial Lipopolysaccharide (LPS) is considered to be the prototypical PAMP. Other PAMPs include bacterial flagellin, lipoteichoic acid from Gram positive bacteria, peptidoglycan, and nucleic acid variants normally associated with viruses, such as double-stranded RNA (dsRNA) or unmethylated CpG motifs. Although the term "PAMP" is relatively new, the concept that molecules derived from microbes must be detected by receptors from multicellular organisms has been held for many decades, and references to an "endotoxin receptor" are found in much of the older literature. Moreover, the term "PAMP" has been criticized on the grounds that most microbes, and not only pathogens, express the molecules that are detected, and so the term MAMP has been proposed (Microbe-associated molecular patterns).