Structure-based drug design of selective 5'-nucleotidases inhibitors
Petr Pachl1, Jiří Brynda1,2, Ivan Rosenberg 2,
Milan Fábry1, Pavlína Řezáčová1,2,
1Institute of Molecular Genetics, Flemingovo nam. 2, Prague 6, Prague, 16610, Czech Republic, 2Institute of Organic Chemistry and Biochemistry AS CR, Flemingovo nam. 2, Prague 6, Prague, 16610, Czech Republic
The monophosphate
5'-nucleotidases, including 5'(3')-deoxyribonucleotidase, belong to a family of
enzymes that catalyze the dephosphorylation of nucleoside monophosphates. The
ribonucleotides and deoxyribonucleotides could be synthesized de novo from low-molecular-weight
precursors or by salvage from nucleosides or nucleobases coming from catabolism
of nucleic acids[1]. In this salvage pathway, ribonucleotides and
deoxyribonucleotides are phosphorylated by nucleoside and nucleotide kinases to
maintain sufficient pools of dNTP's and NTP's for synthesis of DNA and RNA. The
phosphorylation by cellular nucleoside kinases is opposed by 5'-nucleotidases
that dephosphorylate ribo- and deoxyribonucleoside monophosphates[2,3,4].
Besides their role in the regulation of physiological dNTP pools, substrate
cycles between ribonucleotidases and kinases may affect the therapeutic action
of pyrimidine nucleoside analogs used as anticancer and antiviral agents. Such
compounds require the nucleoside kinases activity for phosphorylation to their
active forms. Results of clinical and in
vitro studies propose that an increase in nucleotidase activity can
interfere with nucleoside analogue activation resulting in drug resistance[5].
The main goal of this project is the search for potent and selective inhibitors of mammalian 5'-nucleotidases based on nucleoside phosphonic acids and their derivatives and comparison of sensitivity of 5'-nucleotidases isolated from various sources toward individual inhibitors.
We have prepared 2 types of human 5'-nucleotidase: cytosolic and mitochondrial by recombinant expression in E. coli. The inhibitory properties of a series of nucleoside phosphonic acids derivatives are tested and for the most promising compounds the enzyme-inhibitor structure will be determined to serve as a lead for structure-based drug design efforts.
In general, compounds of strong and selective inhibitory potency are of high medicinal interest as antimetabolites for anticancer and antiviral therapy.
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Hunsucker, B.S. Mitchell, J. Spychala: The 5'-nucleotidases as regulators of
nucleotide and drug metabolism. Pharmacol Ther., 107 (2005), 1-30.
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Bianchi, E. Pontis, P. Reichard: Interrelations between substrate cycles and de
novo synthesis of pyrimidine deoxyribonucleoside triphosphates in 3T6 cells. Proc
Natl Acad Sci U S A, 83 (1986), 986-90.
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Bianchi, E. Fermo, F. Alfinito, C. Vercellati, M. Baserga, F. Ferraro, I.
Guzzo, B. Rotoli, A. Zanella: Molecular characterization of six unrelated
Italian patients affected by pyrimidine 5'-nucleotidase deficiency. Br J
Haematol, 122 (2003), 847-51.
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