Proteomic and metabolomic analyses provide insight into the off-flavour of fruits from citrus trees infected with‘Candidatus Liberibacter asiaticus’  

作　　者：Lixiao Yao Qibin Yu Ming Huang Weilun Hung Jude Grosser Shanchun Chen Yu Wang Frederick G.GmitterJr. 

机构地区：[1]Citrus Research Institute,Southwest University,Chongqing,China [2]Citrus Research and Education Center,University of Florida,Lake Alfred,FL 33850,USA

出　　处：《Horticulture Research》2019年第1期1405-1417,共13页园艺研究（英文）

基　　金：supported by the Florida Citrus Research and Development Foundation(CRDF);the Earmarked Fund for China Agriculture Research System(CARS-27),and China Scholarship Council.

摘　　要：Orange fruit from trees infected by‘Candidatus Liberibacter asiaticus’(CaLas)often do not look fully mature and exhibit off-flavours described as bitter,harsh,and metallic rather than juicy and fruity.Although previous studies have been carried out to understand the effect of CaLas on the flavour of orange juice using metabolomic methods,the mechanisms leading to the off-flavour that occurs in Huanglongbing(HLB)-symptomatic fruit are not well understood.In this study,fruits were collected from symptomatic and healthy Valencia sweet orange(Citrus sinensis)trees grafted on Swingle(C.paradisi X Poncirus trifoliata)rootstock.Isobaric tags for relative and absolute quantification(iTRAQ)and gas chromatography-mass spectrometry(GC-MS)were used to measure the proteins,sugars,organic acids,amino acids,and volatile terpenoids.The results showed that most of the differentially expressed proteins involved in glycolysis,the tricarboxylic acid(TCA)cycle and amino-acid biosynthesis were degraded,and terpenoid metabolism was significantly downregulated in the symptomatic fruit.Valencene,limonene,3-carene,linalool,myrcene,andα-terpineol levels were significantly lower in fruit from CaLas-infected trees than from healthy trees.Similar phenomena were observed for sucrose and glucose.Our study indicated that off-flavour of symptomatic fruit was associated with a reduction in the levels of terpenoid products and the downregulation of proteins in glycolysis,the TCA cycle,and the terpenoid biosynthesis pathway.

关 键 词：orange INSIGHT absolute 

分 类 号：O62[理学—有机化学]