Chlorogenic acid biosynthesis appears linked with suberin production in potato tuber (Solanum tuberosum)

VALIÑAS, M; LANTERI ML; ARJEN TEN HAVE; ANDREU AB

JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

AMER CHEMICAL SOC

Lugar: Washington; Año: 2015 vol. 63 p. 4902 - 4913

0021-8561

Potato (Solanum tuberosum L.) is a good source of dietary antioxidants. Chlorogenic acid (CGA) and caffeic acid(CA) are the most abundant phenolic acid antioxidants in potato and are formed by the phenylpropanoid pathway. A number ofCGA biosynthetic routes that involve hydroxycinnamoyl-CoA quinate hydroxycinnamoyl transferase (HQT) and/orhydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase (HCT) have been proposed, but little is knownabout their path in potato. CA production requires a caffeoyl shikimate esterase (CSE), and CA serves as a substrate of ligninprecursor ferulic acid via the action of caffeic/5-hydroxyferulic acid O-methyltransferase (COMT I). CGA is precursor ofcaffeoyl-CoA and, via caffeoyl-CoA O-methyltransferase (CCoAOMT), of feruloyl-CoA. Feruloyl-CoA is required for lignin andsuberin biosynthesis, crucial for tuber development. Here, metabolite and transcript levels of the mentioned and related enzymes,such as cinnamate 4-hydroxylase (C4H), were determined in the flesh and skin of fresh and stored tubers. Metabolite andtranscript levels were higher in skin than in flesh, irrespective of storage. CGA and CA production appear to occur via pcoumaroyl-CoA, using HQT and CSE, respectively. HCT is likely involved in CGA remobilization toward suberin. The strongcorrelation between CGA and CA, the correspondence with C4H, HQT, CCoAOMT2, and CSE, and the negative correlation ofHCT and COMT I in potato tubers suggest a major flux toward suberin.