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Hydrolysis of Nucleoside Analogues (In vitro)
The pharmacological efficacy of Nucleoside Analogues depends upon their activation by nucleoside kinases as well as on their resistance to hydrolysis. Besides its phosphorylation assaysbased on recombinant Nucleoside Kinases, NOVOCIB proposes a couple of Contract Research Services for evaluating the resistance of nucleoside analogues and of their monophosphorylated to the activity of two major hydrolytic enzymes of the nucleotide metabolism: Purine Nucleoside Phosphorylase and Hypoxanthine-guanine Phosphoribosyltransferase.
The pharmacological efficacy of Nucleoside Analogues depends upon their activation by nucleoside kinases as well as on their resistance to hydrolysis. Besides its phosphorylation assaysbased on recombinant Nucleoside Kinases, NOVOCIB proposes a couple of Contract Research Services for evaluating the resistance of nucleoside analogues and of their monophosphorylated to the activity of two major hydrolytic enzymes of the nucleotide metabolism: Purine Nucleoside Phosphorylase and Hypoxanthine-guanine Phosphoribosyltransferase.
Purine Nucleoside Phosphorylase Cleaving Activity (in vitro)
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Because of its cleaving activity, PNP can represent a threat for therapeutic efficacy of Nucleoside Analogues. In vivo, it can be responsible for the cleavage and the subsequent deactivation of Nucleoside Analogues, then unable to be phosphorylated by nucleoside kinases. The resistance to PNP-catalyzed cleavage may be worth being investigated to increase the therapeutic efficacy of Nucleoside Analogues.
Aim: To evaluate the resistance of Nucleoside Analogues to phosphorolysis catalyzed by human Purine Nucleoside Phosphorylase (PNP).
PNP enzyme: The enzyme used in each of this assay is a human recombinant PNP, cloned by NOVOCIB from human cells, expressed in E. coli, and produced and purified by NOVOCIB (click here for details). PNP purity and activity are controlled before running every assay.
HPLC analysis: The products derived from the phosphorolysis of a nucleoside analogue by Human PNP are identified and quantified by HPLC, in comparison with positive (using inosine) and negative (using adenosine) controls.
Aim: To evaluate the resistance of Nucleoside Analogues to phosphorolysis catalyzed by human Purine Nucleoside Phosphorylase (PNP).
PNP enzyme: The enzyme used in each of this assay is a human recombinant PNP, cloned by NOVOCIB from human cells, expressed in E. coli, and produced and purified by NOVOCIB (click here for details). PNP purity and activity are controlled before running every assay.
HPLC analysis: The products derived from the phosphorolysis of a nucleoside analogue by Human PNP are identified and quantified by HPLC, in comparison with positive (using inosine) and negative (using adenosine) controls.
To know more about NovoCIB's service for PNP-catalyzed phosphorolysis resistance assay.
Hypoxanthine-guanine Phosphoribosyltransferase Cleaving Activity (in vitro)
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Because of its pyrophosphorolysis activity, HGPRT can represent a threat for therapeutic efficacy of Nucleoside Analogues. NOVOCIB's HPRT resistance assay consists in treating by HGPRT, in the presence of PPi, a monophosphorylated nucleotide analogue (click here for nucleoside analogue phosphorylation assay services). Pyrophosphorolysis reaction is then checked by HPLC analysis of the products, in parallel with a positive control provided by HGPRT-catalyzed pyrophosphorolysis of IMP.
Aim: Screening of compounds for their resitance to pyrophosphorolysis catalyzed by HGPRT
HGPRT enzyme: The enzyme used in this assay is a human recombinant HGPRT, cloned by NOVOCIB from human cells, expressed in E. coli, and produced and purified by NOVOCIB (click here for details). HGPRT purity and activity are controlled before running every assay.
HPLC analysis: The products derived from the pyrophosphorolysis of a nucleoside analogue by Human HGPRT are identified and quantified by HPLC, in comparison with positive control, using inosine monophosphate (IMP).
Aim: Screening of compounds for their resitance to pyrophosphorolysis catalyzed by HGPRT
HGPRT enzyme: The enzyme used in this assay is a human recombinant HGPRT, cloned by NOVOCIB from human cells, expressed in E. coli, and produced and purified by NOVOCIB (click here for details). HGPRT purity and activity are controlled before running every assay.
HPLC analysis: The products derived from the pyrophosphorolysis of a nucleoside analogue by Human HGPRT are identified and quantified by HPLC, in comparison with positive control, using inosine monophosphate (IMP).
To know more about NovoCIB's service for HGPRT-catalyzed pyrophosphorolysis resistance assay.