title: The N terminus of bacterial elongation factor Tu elicits innate immunity in Arabidopsis plants.
abstract: 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.
authors.affiliation: Zürich-Basel Plant Science Center, Botanisches Institut der Universität Basel, CH-4056 Basel, Switzerland.
authors.forename: Gernot
authors.initials: G
authors.lastname: Kunze
authors.forename: Cyril
authors.initials: C
authors.lastname: Zipfel
authors.forename: Silke
authors.initials: S
authors.lastname: Robatzek
authors.forename: Karsten
authors.initials: K
authors.lastname: Niehaus
authors.forename: Thomas
authors.initials: T
authors.lastname: Boller
authors.forename: Georg
authors.initials: G
authors.lastname: Felix
mesh_terms: D000107:Acetylation; D000595:Amino Acid Sequence / Q000502:physiology; D017360:Arabidopsis / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology; D004926:Escherichia coli / Q000737:chemistry; D005030:Ethylenes / Q000096:biosynthesis; D005408:Flagellin / Q000737:chemistry / Q000378:metabolism; D007113:Immunity, Innate / Q000187:drug effects / Q000502:physiology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010444:Peptide Elongation Factor Tu / Q000737:chemistry* / Q000302:isolation & purification / Q000502:physiology*; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D010935:Plant Diseases / Q000382:microbiology; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D005030:Ethylenes; D010446:Peptide Fragments; D005408:Flagellin; C036216:ethylene; D010444:Peptide Elongation Factor Tu