Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.1.4 (deaminase)
 5,113 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new potent inhibitor of adenosine deaminase (co-vidarabine) was used in combination studies with adenine arabinoside (vidarabine, Vira-ATM) to protect this purine nucleoside from enzymatic deamination to the more weakly active metabolite, hypoxanthine arabinoside. Comparing the combination to vidarabine alone, a significant increase (10-fold) of the antiviral activity of the combined drugs was observed against herpes and vaccinia viruses in tissue culture and subcutaneously, against cranial herpesvirus infections in mice. Several other investigators have also recently reported several-fold enhancement of vidarabine activity by newly described deaminase inhibitors. They observed that plaque formation by several large DNA-containing viruses (herpes, vaccinia, varicella zoster) and an RNA-containing oncogenic virus was markedly prevented by the combination compared to vidarabine alone. In animals, enhanced protection (increased survivors) and/or highly significant increase in the life span of dying mice treated with the 2-drug combination, was also observed compared to vidarabine administered singly. These observations in animals clearly indicate that combination studies with vidarabine (Vira-ATM) and co-vidarabine (deaminase inhibitor) deserve serious consideration as future therapy for systemic virus infections in man including herpesvirus encephalitis.
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PMID:Effect of a novel adenosine deaminase inhibitor (co-vidarabine, co-V) upon the antiviral activity in vitro and in vivo of vidarabine (Vira-Atm) for DNA virus replication. 21 90

The RNA-specific adenosine deaminase (ADAR1) is an interferon-inducible editing enzyme that converts adenosine to inosine. ADAR1 contains three distinct domains: a N-terminal Z-DNA binding domain that includes two Z-DNA binding motifs; a central double-stranded RNA binding domain that includes three dsRNA binding motifs (dsRBM); and a C-terminal catalytic domain responsible for A-to-I enzymatic activity. The E3L protein of vaccinia virus mediates interferon resistance. E3L, similar to ADAR1, also contains Z-DNA binding and dsRNA binding motifs. To assess the possible role of E3L in modulating RNA editing by ADAR1, we examined the effect of E3L on ADAR1 deaminase activity. Wild-type E3L protein was a potent inhibitor of ADAR1 deaminase enzymatic activity. Analysis of mutant E3L proteins indicated that the carboxy-proximal dsRBM of E3L was essential for antagonism of ADAR1. Surprisingly, disruption of the Z-DNA binding domain of E3L by double substitutions of two highly conserved residues also abolished its antagonistic activity, whereas deletion of the entire Z domain had little effect on the inhibition. With natural neurotransmitter pre-mRNA substrates, E3L weakly inhibited the site-selective editing activity by ADAR1 at the R/G site of the glutamate receptor B subunit (GluR-B) pre-mRNA and the A site of serotonin 2C receptor (5-HT2CR) pre-mRNA; editing of the intronic hotspot (+)60 site of GluR-B was not affected by E3L. These results demonstrate that the A-to-I RNA editing activity of the IFN-inducible adenosine deaminase is impaired by the product of the vaccinia virus E3L interferon resistance gene.
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PMID:Vaccinia virus E3L interferon resistance protein inhibits the interferon-induced adenosine deaminase A-to-I editing activity. 1168 59

Of the vaccinia virus genes that are conserved in all sequenced poxviruses, each one except for VACWR084 (G6R) has been at least partially characterized. The poxvirus protein encoded by G6R belongs to the NlpC/P60 superfamily, which consists of proteins with a papain-like fold and known or predicted protease, amidase or acyltransferase activity. The G6 protein was synthesized late in infection and localized to the interior of virions, primarily between the membrane and core. Unlike other conserved poxvirus genes, G6R was not required for virus propagation and spread in a variety of cells. Nevertheless, G6R null mutants caused less severe disease in mice than the parent or revertant virus. Moreover, mutation of the predicted catalytic cysteine led to the same level of attenuation as a null mutant, suggesting that the G6 protein has enzymatic activity that is important in vivo. Conservation of G6R amongst poxviruses and the disparity between its role in vitro and in vivo imply that the protein is involved in an aspect of the virus-host interaction that is common to vertebrates and insects.
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PMID:A conserved poxvirus NlpC/P60 superfamily protein contributes to vaccinia virus virulence in mice but not to replication in cell culture. 1828 Oct 72