Fluoride is a strong and specific inhibitor of (asymmetrical) Ap4A hydrolases.
Fluoride acts as a noncompetitive, strong inhibitor of (asymmetrical) Ap4A hydrolases (EC 3.6.1.17). The Ki values estimated for the enzymes isolated from seeds of some higher plants (yellow lupin, sunflower and marrow) are in the range of 2-3 microM and I50 for the hydrolase from a mammalian tissue (beef liver) is 20 microM. The anion, up to 25 mM, does not affect the following other enzymes which are able to degrade the bis(5'-nucleosidyl)-oligophosphates: Escherichia coli (symmetrical) Ap4A hydrolase (EC 3.6.1.41), yeast Ap4A phosphorylase (EC 2.7.7.53), yellow lupin Ap3A hydrolase (EC 3.6.1.29) and phosphodiesterase (EC 3.1.4.1). None of halogenic anions but fluoride affects the activity of (asymmetrical) Ap4A hydrolases. Usefulness of the fluoride effect for the in vivo studies on the Ap4A metabolism is shortly discussed.
Guranowski
A
A
Katedra Biochemii, Akademia Rolnicza, Poznań, Poland.
D017766:Acid Anhydride Hydrolases; D005459:Fluorides / Q000494:pharmacology*; D007700:Kinetics; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors*; D010944:Plants / Q000187:drug effects / Q000201:enzymology*; D012639:Seeds / Q000187:drug effects / Q000201:enzymology*; D013379:Substrate Specificity
D010744:Phosphoric Monoester Hydrolases; D017766:Acid Anhydride Hydrolases; C020023:bis(5'-nucleosyl)tetraphosphatase (asymmetrical); D005459:Fluorides