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Comparison of enzymes involved in sugar metabolism from Shang‐24 ( Vinifera quinguangularis ) and Cabernet Sauvignon ( Vinifera vinifera ) at veraison
Author(s) -
PAN Q.H.,
CAO P.,
DUAN C.Q.
Publication year - 2009
Publication title -
australian journal of grape and wine research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.65
H-Index - 77
eISSN - 1755-0238
pISSN - 1322-7130
DOI - 10.1111/j.1755-0238.2008.00030.x
Subject(s) - veraison , vitis vinifera , invertase , sugar , chemistry , wine , fructose , amylase , fructokinase , enzyme , biochemistry , food science , botany , biology
Background and Aims: Sugar is a main contributor to the quality of grape berries, but little is known about the characteristics of sugar metabolism in Chinese wild grapes. Here, enzymes related to sugar metabolism were investigated in berries of both Shang‐24 ( Vitis quinguangularis Rehd), a wild grape native to China, and Cabernet Sauvignon ( V. vinifera L.). Methods and Results: Analyses using high performance liquid chromatography and spectrophotometer showed that Shang‐24 contained lower levels of glucose and fructose, compared with Cabernet Sauvignon, but had higher activities of enzymes related to sugar hydrolysis, particularly soluble acid invertase (SAI) and β‐amylase. Analyses of enzyme kinetics, enzyme‐linked immunosorbent assay and Western blot revealed that SAI and β‐amylase in Shang‐24 had low K m values and that high levels of both enzymes were present. Furthermore, a novel peptide of SAI of 105 kDa was detected in Shang‐24 along with a peptide of 60 kDa that also was present in Cabernet Sauvignon. Conclusions: It is thus suggested that biochemical characteristics of SAI and β‐amylase in Shang‐24 differ from those in Cabernet Sauvignon, and the novel peptide may be related to high activity of SAI in Shang‐24. Significance of the Study: These data provide an essential basis for further study of the genetic regulation of sugar and its metabolism in grape berries.