title: Inhibition of eukaryotic dna polymerase alpha by persimmon (Diospyros kaki) extract and related polyphenols.
abstract: The effects of persimmon extract (Diospyros kaki) and related polyphenols on eukaryotic DNA polymerase alpha were examined. It was found that persimmon extract, epigallocatechin gallate, and epicatechin gallate strongly inhibited the activity of DNA polymerase alpha purified from calf thymus. Among these polyphenols, persimmon extract had the most potent effect on DNA polymerase alpha activity and the concentration of persimmon extract producing 50% inhibition of the activity was 0.191 microM. Persimmon extract showed a weaker effect on DNA polymerase beta and slightly inhibited primase and DNA polymerase I. The inhibition of DNA polymerase alpha by persimmon extract was competitive with the template-primer and noncompetitive with dTTP substrate. The Ki value of DNA polymerase alpha for persimmon extract was estimated to be 70 nM. Moreover, persimmon extract inhibited [3H]thymidine incorporation of human peripheral lymphocyte cells stimulated by PHA.
authors.affiliation: Department of Agricultural Chemistry, Faculty of Bioresources, Mie University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Umekawa
authors.forename: Y
authors.initials: Y
authors.lastname: Takada
authors.forename: Y
authors.initials: Y
authors.lastname: Furuichi
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: Y
authors.initials: Y
authors.lastname: Achiwa
authors.forename: T
authors.initials: T
authors.lastname: Komiya
authors.forename: S
authors.initials: S
authors.lastname: Yoshida
mesh_terms: D004256:DNA Polymerase I / Q000037:antagonists & inhibitors* / Q000097:blood; D019951:DNA Polymerase beta / Q000037:antagonists & inhibitors / Q000097:blood; D019915:DNA Primase / Q000037:antagonists & inhibitors / Q000097:blood; D005057:Eukaryotic Cells / Q000378:metabolism; D005419:Flavonoids; D006801:Humans; D020128:Inhibitory Concentration 50; D007700:Kinetics; D010636:Phenols / Q000494:pharmacology*; D010940:Plant Proteins / Q000494:pharmacology*; D011108:Polymers / Q000494:pharmacology*; D059808:Polyphenols
chemical_list: D005419:Flavonoids; D010636:Phenols; D010940:Plant Proteins; D011108:Polymers; D059808:Polyphenols; D019915:DNA Primase; D004256:DNA Polymerase I; D019951:DNA Polymerase beta