N terminus of bacterial elongation factor Tu elicits innate immunity in Arabidopsis plants

• Published in: The Plant cell 2004-12, Vol.16 (12), p.3496-3507
• Main Authors: Kunze, G, Zipfel, C, Robatzek, S, Niehaus, K, Boller, T, Felix, G
• Format: Article
• Language: English
• Subjects: Acetylation; Agrobacterium tumefaciens; Amino Acid Sequence - physiology; Amino acids; Arabidopsis - drug effects; Arabidopsis - metabolism; Arabidopsis - physiology; Arabidopsis thaliana; Bacteria; bacterial proteins; Bacterial Proteins - chemistry; Bacterial Proteins - isolation & purification; Bacterial Proteins - physiology; binding proteins; Biosynthesis; Brassicaceae; defense mechanisms; E coli; elongation factor Tu; Epitopes; Escherichia coli; Escherichia coli - chemistry; ethylene; Ethylenes - biosynthesis; Flagellin - chemistry; Flagellin - metabolism; Immunity, Innate - drug effects; Immunity, Innate - physiology; induced resistance; Innate immunity; Leaves; Models, Molecular; Molecular Sequence Data; oxidative burst; pathogen-associated molecular patterns; Peptide Elongation Factor Tu - chemistry; Peptide Elongation Factor Tu - isolation & purification; Peptide Elongation Factor Tu - physiology; Peptide elongation factors; Peptide Fragments - chemistry; Peptide Fragments - metabolism; Peptide Fragments - pharmacology; Plant cells; Plant Diseases - microbiology; Plant Leaves - drug effects; Plant Leaves - metabolism; plant pathogenic bacteria; Plants; Protein Structure, Tertiary - physiology; Proteins; Pseudomonas syringae pv. tomato; Ralstonia solanacearum; Receptors; Sinorhizobium meliloti; synthetic peptides
• ISSN: 1040-4651; 1532-298X
• DOI: 10.1105/tpc.104.026765

Innate immunity is based on the recognition of pathogen-associated molecular patterns (PAMPs). Here, we show that elongation factor Tu (EF-Tu), the most abundant bacterial protein, acts as a PAMP in Arabidopsis thaliana and other Brassicaceae. EF-Tu is highly conserved in all bacteria and is known to be N-acetylated in Escherichia coli. Arabidopsis plants specifically recognize the N terminus of the protein, and an N-acetylated peptide comprising the first 18 amino acids, termed elf18, is fully active as inducer of defense responses. The shorter peptide, elf12, comprising the acetyl group and the first 12 N-terminal amino acids, is inactive as elicitor but acts as a specific antagonist for EF-Tu-related elicitors. In leaves of Arabidopsis plants, elf18 induces an oxidative burst and biosynthesis of ethylene, and it triggers resistance to subsequent infection with pathogenic bacteria.