Open AccessAmino Acid Sequence of Bacterial Microbe-Associated Molecular Pattern flg22 Is Required for Virulence
Author(s) -
Naito Kurio,
Fumiko Taguchi,
Tomoko Suzuki,
Yoshishige Inagaki,
Kazuhiro Toyoda,
Takeshi Shiraishi,
Yuki Ichinose
Publication year - 2008
Publication title -
molecular plant-microbe interactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.565
H-Index - 153
eISSN - 1943-7706
pISSN - 0894-0282
DOI - 10.1094/mpmi-21-9-1165
Subject(s) - flagellin , pseudomonas syringae , biology , mutant , elicitor , microbiology and biotechnology , virulence , flagellum , bacteria , biochemistry , pathogen , genetics , gene
Flagellin proteins derived from Pseudomonas syringae pv. tabaci 6605 and flg22 Pa (QRLSTGSRINSAKDDAAGLQIA), one of the microbe-associated molecular patterns (MAMP) in bacterial flagellin, induce cell death and growth inhibition in Arabidopsis thaliana. To examine the importance of aspartic acid (D) at position 43 from the N-terminus of a flagellin in its elicitor activity, D43 was replaced with valine (V) and alanine (A) in P. syringae pv. tabaci flagellin and flg22 Pta . The abilities of flagellins from P. syringae pv. tabaci D43V and D43A to induce cell death and growth inhibition were reduced, whereas the abilities of flg22 Pta D43V and flg22 Pta D43A were abolished. These results indicate that D43 is important for elicitor activity in P. syringae pv. tabaci. When tobacco plants were inoculated with each bacterium by the spray method, both P. syringae pv. tabaci D43V and D43A mutants had remarkably reduced ability to cause disease symptoms. Both mutants had reduced or no swimming and swarming motilities and adhesion ability. In P. syringae pv. tabaci D43V, little flagellin protein was detected and few flagella were observed by electron microscopy. These results indicate that mutant flagella are unstable and that flagellar motility is impaired. Thus, the amino acid residue required for MAMP activity is important for the intrinsic flagellar function.