Fatty acids bind to the fungal elicitor cryptogein and compete with sterols.
Cryptogein is a proteinaceous elicitor of plant defense reactions which also exhibits sterol carrier properties. In this study, we report that this protein binds fatty acids. The stoichiometry of the fatty acid-cryptogein complex is 1:1. Linoleic acid and dehydroergosterol compete for the same site, but elicitin affinity is 27 times lower for fatty acid than for sterol. We show that C7 to C12 saturated and C16 to C22 unsaturated fatty acids are the best ligands. The presence of double bonds markedly increases the affinity of cryptogein for fatty acids. A comparison between elicitins and known lipid transfer proteins is discussed.
UMR 692 INRA, Université de Bourgogne, Laboratoire de Phytopharmacie et de Biochimie des Interactions Cellulaires, France.
H
H
Osman
V
V
Mikes
M L
ML
Milat
M
M
Ponchet
D
D
Marion
T
T
Prangé
B F
BF
Maume
S
S
Vauthrin
J P
JP
Blein
D020418:Algal Proteins / Q000378:metabolism; D001667:Binding, Competitive; D004875:Ergosterol / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D019787:Linoleic Acid / Q000494:pharmacology; D010838:Phytophthora / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins; D013261:Sterols / Q000378:metabolism*; D013329:Structure-Activity Relationship
D020418:Algal Proteins; D005227:Fatty Acids; D005656:Fungal Proteins; D011506:Proteins; D013261:Sterols; C061032:cryptogein protein, Phytophthora cryptogea; C085101:elicitin, Phytophthora; C010905:dehydroergosterol; D019787:Linoleic Acid; D004875:Ergosterol