Functional characterization of two 13-lipoxygenase genes from olive fruit in relation to the biosynthesis of volatile compounds of virgin olive oil.
Two LOX cDNA clones, Oep1LOX2 and Oep2LOX2, have been isolated from olive ( Olea europaea cv. Picual). Both deduced amino acid sequences showed significant similarity to known plant LOX2, and they contain an N-terminal chloroplastic transit peptide. Genomic Southern blot analyses suggest that at least three copies of Oep1LOX2 and one copy of Oep2LOX2 should be present in the olive genome. Linolenic acid proved to be the preferred substrate for both olive recombinant LOXs, and analyses of reaction products revealed that both enzymes produce primarily 13-hydroperoxides from linoleic and linolenic acids. Expression levels of both genes were measured in the mesocarp and seeds during development and ripening of Picual and Arbequina olive fruit along with the level of volatile compounds in the corresponding virgin olive oils. Biochemical and gene expression data suggest a major involvement of the Oep2LOX2 gene in the biosynthesis of virgin olive oil aroma compounds.
Padilla
María N
MN
Department of Physiology and Technology of Plant Products, Instituto de la Grasa (CSIC), Seville, Spain.
Hernández
M Luisa
ML
Sanz
Carlos
C
Martínez-Rivas
José M
JM
D000595:Amino Acid Sequence; D018744:DNA, Plant / Q000737:chemistry / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics; D005638:Fruit / Q000201:enzymology / Q000235:genetics*; D015870:Gene Expression; D008084:Lipoxygenase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018551:Solanum lycopersicum / Q000235:genetics; D008969:Molecular Sequence Data; D009812:Odorants / Q000032:analysis*; D031658:Olea / Q000235:genetics*; D000069463:Olive Oil; D010938:Plant Oils / Q000737:chemistry*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D011198:Solanum tuberosum / Q000235:genetics; D013379:Substrate Specificity; D014835:Volatilization; D017962:alpha-Linolenic Acid / Q000378:metabolism
D018744:DNA, Plant; D000069463:Olive Oil; D010938:Plant Oils; D011994:Recombinant Proteins; D017962:alpha-Linolenic Acid; C117433:13-lipoxygenase; D008084:Lipoxygenase