Biochemical, molecular and structural analysis of multiple thaumatin-like proteins from the elderberry tree (Sambucus nigra L.).
Thaumatin-like proteins (TLPs) were isolated and characterized from fruits and leaves of elderberry (Sambucus nigra) and their corresponding genes cloned. In addition, the developmental regulation and induction of the different TLPs was followed in some detail. Ripening berries accumulated a fruit-specific TLP during the final stages of maturation. This fruit-specific TLP had no antifungal activity and was devoid of beta-glucanase activity. Leaves constitutively expressed a TLP that closely resembled the fruit-specific homologue. Treatment with jasmonate methyl ester induced two additional TLPs in leaves but did not induce or enhance the expression of TLPs in immature berries. In contrast to jasmonate methyl ester, both ethephon and garlic extract induced the expression of a TLP in unripe berries that normally do not express any TLP. Sequence analysis and molecular modeling indicated that all elderberry thaumatin-like proteins share a high sequence similarity with group-5 pathogenesis-related proteins. However, the proteins encoded by the different sequences differed from each other in isoelectric point and the distribution of the charges on the surface of the molecule.
Van Damme
Els J M
EJ
Laboratory for Phytopathology and Plant Protection, Katholieke Universiteit Leuven, Willem de Croylaan 42, 3001, Belgium. els.vandamme@agr.kuleuven.ac.be
Charels
Diana
D
Menu-Bouaouiche
Laurence
L
Proost
Paul
P
Barre
Annick
A
Rougé
Pierre
P
Peumans
Willy J
WJ
D000085:Acetates / Q000494:pharmacology; D000595:Amino Acid Sequence; D000890:Anti-Infective Agents / Q000494:pharmacology; D003001:Cloning, Molecular; D003517:Cyclopentanes / Q000494:pharmacology; D018076:DNA, Complementary; D005638:Fruit / Q000235:genetics* / Q000378:metabolism; D005658:Fungi / Q000187:drug effects; D005737:Garlic / Q000737:chemistry; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009943:Organophosphorus Compounds / Q000494:pharmacology; D054883:Oxylipins; D010936:Plant Extracts / Q000494:pharmacology; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D027924:Sambucus nigra / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D000085:Acetates; D000890:Anti-Infective Agents; D003517:Cyclopentanes; D018076:DNA, Complementary; D009943:Organophosphorus Compounds; D054883:Oxylipins; D010936:Plant Extracts; D010940:Plant Proteins; C072239:methyl jasmonate; D004693:Glucan Endo-1,3-beta-D-Glucosidase; C005073:ethephon