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Updated: Jul 10, 2025
Spectrophotometric Methods for the Study of Eukaryotic Glycogen Metabolism
Published on: August 19, 2021
Discovery and biochemical characterization of two hexokinases from Crassostrea gigas
Huibo Song1, Bo Wang2, Guihong Zhao2
1College of Agricultural and Biological Engineering (College of Tree Peony), Heze University, Heze, 274015, China; Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
Abstract:
Hexokinases (HKs) play a vital role in glucose metabolism, which controls the first committed step catalyzing the production of glucose-6-phosphate from glucose. Two HKs (CGIHK1 and CGIHK2) from the Pacific oyster Crassostrea giga were cloned and characterized. CGIHK1 and CGIHK2 were recombinantly expressed in Escherichia coli and successfully purified by the Ni-NTA column. The optimum pH of the two enzymes was pH 8.0 and 8.5, respectively. The optimum temperature of the two enzymes was 42 °C and 50 °C, respectively. Both enzymes showed a clear requirement for divalent magnesium and were strongly inhibited by SDS. CGIHK1 exhibited highly strict substrate specificity to glucose, while CGIHK2 could also catalyze other 11 monosaccharide substrates. This is the first report on the in vitro biosynthesis of glucose-6-phosphate by the hexokinases from Crassostrea gigas. The facile expression and purification procedures combined with different substrate specificities make CGIHK1 and CGIHK2 candidates for the biosynthesis of glucose-6-phosphate and other sugar-phosphates.
