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Secondary Metabolites. Products that are not essential for normal growth and development of plants Natural productsMultiple functions throughout the plant's life cycle. Secondary metabolites. Functions and Applications of Secondary Metabolites. An interesting target for plant breeding and genetic engineering.
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1. Characterization of Acyltransferases in Plant Secondary Metabolism
2. Secondary Metabolites Products that are not essential for normal growth and development of plants
Natural products
Multiple functions throughout the plant’s life cycle
3. Functions and Applications of Secondary Metabolites
4. Genetic Engineering of 2’ Metabolic Pathway Aims to either increase or decrease the quantity of a certain compound
1. Change the expression of regulatory genes
=> regulation of multiple biosynthesis genes
2. Control the expression of one or a few structural genes
=> overcoming specific rate-limiting steps in the pathway
5. Acyltransferases
Acylation
The process of adding an acyl group to a compound
The structural and functional modification of compounds
Acyltransferases
A group of enzymes catalyzing the transfer of acyl groups
A powerful means for engineering of secondary metabolites
6. Versatile Acyltransferase (VAT) Family Protein family consisting of acyltransferases in secondary metabolism in plants and fungi
Motif 1 (HXXXD):a general acid/base catalyst
Motif 2:unknown function
Motif 3 (DFGWG):catalytic activity
7. Molecular Phylogenetic Tree of VAT
8. Characterization of VATs Benzylalcohol acyltransferae (BEAT)
Deacetylvindoline 4-O-acetyltransferase (DAT)
Strawberry alcohol acyltransferase (SAAT)
Anthocyanin acyltransferases (AAT)
9. BEAT Benzylacetate
A type of benzoid esters
A major constituent of the floral scent of Clarkia breweri
Important flavorants in ripe fruit and ingredients in perfumes
Benzylalcohol acyltransferase (BEAT)
Catalysis the formation of the ester bezylacetate
10. Isolation of BEAT Genes
11. Analysis of BEAT Activity
12. Expression of BEAT
13. DAT Vindoline
Monoterpenoid indole alkaloids
Use in cancer chemotherapy
Low yields in the plant
Deacetylvindoline
4-O-acetyltransferase (DAT)
Catalysis of the last step in vindoline biosynthesis
14. Isolation of DAT Gene
15. Chemical Modification of DAT
16. Light Induction of DAT Activity
17. SAAT Volatile esters
Production form all soft fruit species during ripening
Flavor components of the majority of fruits
Source of energy, vitamins, minerals and antioxidants
Strawberry alcohol acyltransferase (SAAT)
Catalysis of transacylation from acyl-CoA to an alcohol
Key enzyme in aroma biochemistry
Use of the last step in volatile esters biosynthesis
18. Isolation of the SAAT Gene
19. Analysis of SAAT Gene Expression
20. Functional Expression of SAAT
21. AAT in Salvia splendens Anthocyanin
The largest subclass of plant flavonoid
Attracting pollinators
Protection of plants from various stresses
Safety to human health
Anthocyanin acyltransferases (AAT)
Catalyze the acyl transfer from acyl-CoA to the sugar moiety of anthocyanin
22. Isolation of AAT gene
23. Analysis of Ss5MaT gene expression
24. Applications of Acyltransferases Heterologous expressions
Transformation SAAT gene of strawberry fruit into petunia leaves
Metabolic engineering to modify flower color
blue rose
Modification of the functional and structural properties
Only research for acyltransferase related to flavor and pigment
..
25. Future Prospects
26. References
Acetyl-CoA:benzylalcohol acetyltransferase – an enzyme involved in floral scent production in Clarkia breweri., Natalia Dudareva, John C. D’Auria,Kyoung Hee Nam, Eran Pichersky, The Plant Journal, 1998, February, 297-304
The termial O-acetyltransferase involved in vindoline biosynthesis defines a new class of proteins responsible for coenzyme A-dependent acyl transfer., Venoit St-Pierre, Pierre Laflamme, Anne-Marie Alarco, Vincenzo De Luca, The plant Journal, 1998, March, 703-713
Identification of the SAAT gene involved in strawberry flavor biogenesis by use of DNA microarrays., Asaph Aharoni, Lepold C. P. Keizer, Harro J. Bouwmeester, Ann P. O’Connell., The Plant Cell, 2000, May, 647-661
Engineering secondary metabolite production in plants., R. Verpoorte and J. Memelink, Current Opinion in Biotechnology, 2000, May, 181-187
Anthocyanin acyltransferases: specificities, mechanism, phylogenetics, and applications., Toru Nakayama, Hirokazu Suzuki, Tokuzo Nishino, Journal of Molecular Catalysis B: Enzymatic, 2003, March, 117–132
Identification and characterization of a novel anthocyann malonyltransferase from scarlet sage (Salvia splendens) flowers., Hirokazu Suzuki, Shin’ya Sawade, Kazufumi Watanabe,Tokuzo Nishino, The Plant Journal, 2004, March, 994-1003