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Characterization of Genes Involved in the Formation of Aroma Volatiles in "Charentais" Melon Fruit
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Edité par CCSD -
International audience. Volatiles esters impart distinct characteristics to the fruit quality."Charentais" cantaloupe melon (Cucumis melo "cantalupensis") is characterized byabundant sweetness and aromatic flavour. Plant alcohol acyl transferase (AAT)genes have been identified and shown to be involved in aromas production. Recently,two cDNAs (Cm-AAT1 and Cm-AAT2) putatively involved in the formation of aroma volatile esters have been isolated from melon fruit. Cm-AAT1 protein exhibit alcohol acyl transferase activity while no such activity could be detected for Cm-AAT2. Two new cDNAs (Cm-AAT3 and Cm-AAT4) have been isolated from melon fruit thatshowed 69% and 36% similarity, respectively, with Cm-AAT1. The percentagesimilarity over the whole amino acid sequence between them is 34%. Cm-AAT3 andCm-AAT4 show the highest similarity to the tobacco Nt-HSR201 protein and a rosealcohol acyltransferase Rh-AAT1, respectively. All Cm-AATs genes, share threeconserved regions common to the BAHD acyltransferase gene superfamily.Heterologous expression in yeast revealed that some of the encoded proteins have awide range of specificity while others are specific to a narrow range of substrates.