Changes in shikimate dehydrogenase and the end products of the shikimate pathway, chlorogenic acid and lignins, during the early development of seedlings of Capsicum annuum

Abstract

SUMMARYThe developmental regulation and organ-specific expression of shikimate dehydrogenase was studied in seedlings of Capsicum annuum L. during their early development. The results obtained suggest that there is both a developmental regulation and an organ-specific expression of shikimate dehydrogenase in seedlings of C. annuum, seen mainly in the cotyledons. For example, shikimate dehydrogenase isoenzyme 3 was differentially expressed in cotyledons, but not at all in roots or hypocotyls. When the amounts of shikimate dehydrogenase were compared with the end-products of the shikimate pathway, chlorogenic acid and lignins, it was observed that the fall in shikimate dehydrogenase activity in cotyledons coincided with a decrease in the concentrations of phenolics during primary leaf development. However, this did not seem to be the case with the hypocotyls, where the fall in phenolics was not related to the amount of shikimate dehydrogenase but rather to an increase in lignin deposition, supporting the view that chlorogenic acid might act as a precursor of the aromatic moiety of cinnamoyl alcohols during cell wall ligniflcation.

Low levels of ribosomal RNA partly account for the very high photosynthetic phosphorus‐use efficiency of Proteaceae species

“…While activities of most enzymes were low in young expanding leaves, these leaves showed relatively high levels of SKDH, which may be involved in the synthesis of the red and yellow pigments, assuming these are phenolics (Díaz et al . ; Peek et al . ).…”

Methyl Jasmonate and Salicylic Acid Induced Oxidative Stress and Accumulation of Phenolics in Panax ginseng Bioreactor Root Suspension Cultures

“…The reaction was initiated by the addition of extract and increase in absorbance at 340 nm (ε, 6.22 mM −1 cm −1 ) was recorded. The SKDH (EC 1.1.1.25) assay was performed in a reaction medium containing shikimic acid (2 mM) and NADP (0.5 mM) in Tris-HCl buffer (pH 9.0, 0.1 M) [43]. The reaction was initiated by the addition of extract and increase in absorbance at 340 nm (ε, 6.22 mM −1 cm −1 ) was recorded following the NADP reduction.…”

Enhancement of phenylpropanoid enzymes and lignin in Phalaenopsis orchid and their influence on plant acclimatisation at different levels of photosynthetic photon flux

“…G-6-PDH activity (EC 1.1.1.49) was measured in 50 mm Tris-HCl (pH 7.4) containing 5 mm MgCl 2 , 0.5 mm glucose 6 phosphates and 0.5 mm NADP (Debnam and Emes 1999). The SKDH (EC 1.1.1.25) assay was performed following the method of Díaz et al (1997). CAD (EC 1.1.1.195) assay was performed following the method of Mitchell et al (1994).…”