A psychrophilic fungal strain of Geomyces pannorum P15 was screened for its ability to utilize a range of synthetic and natural organophosphonate compounds as the sole source of phosphorus, nitrogen, or carbon. Only phosphonoacetic acid served as a phosphorus source for microbial growth in phosphate-independent manner. Substrate metabolism did not lead to extracellular release of inorganic phosphate. No phosphonate metabolizing enzyme activity was detectable in cell-free extracts prepared from Geomyces biomass pregrown on 2 mmol/L phosphonoacetic acid.

• MeSH
• Ascomycota růst a vývoj   metabolismus   MeSH
• dusík metabolismus   MeSH
• fosfáty metabolismus   MeSH
• fosfor metabolismus   MeSH
• kyselina fosfonoctová metabolismus   MeSH
• uhlík metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• dusík MeSH
• fosfáty MeSH
• fosfor MeSH
• kyselina fosfonoctová MeSH
• uhlík MeSH

The antiviral efficacy of phosphonoformic acid (PFA) was examined on tissue cultures of the human embryonal lungs against the viruses herpes simplex type 1 and 2, herpes zoster, and the human cytomegalovirus using the method of the inhibition of the cytopathic effect and against herpes simplex type 1 and 2 on the tissue cultures of Vero cells using the methods of the inhibition of plaque formation. PFA was demonstrated to inhibit the reproduction of the viruses under study in both tests on tissue cultures. In persistence studies, the cytomegalovirus was not isolated back from the cells of the human embryonal lungs, which gave evidence of its greater sensitivity to PFA. In in vivo experiments, PFA in the form of a 3% ointment suppressed herpetic dermatitis on the guinea-pig skin, when treatment started 6, 24 and 48 hours after infection. In a preliminary experiment on rabbit corneas, an ointment with 3% PFA inhibited herpetic keratoconjunctivitis in time intervals of 1 and 3 hours after infection.

• MeSH
• antivirové látky farmakologie   terapeutické užití   MeSH
• foskarnet MeSH
• Herpesviridae účinky léků   MeSH
• herpetické infekce farmakoterapie   MeSH
• králíci MeSH
• kyselina fosfonoctová analogy a deriváty   farmakologie   terapeutické užití   MeSH
• morčata MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• morčata MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• antivirové látky MeSH
• foskarnet MeSH
• kyselina fosfonoctová MeSH

Despite the eradication of smallpox four decades ago, poxviruses continue to be a threat to humans and animals. The arsenal of anti-poxvirus agents is very limited and understanding mechanisms of resistance to agents targeting viral DNA polymerases is fundamental for the development of antiviral therapies. We describe here the phenotypic and genotypic characterization of poxvirus DNA polymerase mutants isolated under selective pressure with different acyclic nucleoside phosphonates, including HPMPC (cidofovir), cHPMPC, HPMPA, cHPMPA, HPMPDAP, HPMPO-DAPy, and PMEO-DAPy, and the pyrophosphate analogue phosphonoacetic acid. Vaccinia virus (VACV) and cowpox virus drug-resistant viral clones emerging under drug pressure were characterized phenotypically (drug-susceptibility profile) and genotypically (DNA polymerase sequencing). Different amino acid changes in the polymerase domain and in the 3'-5' exonuclease domain were linked to drug resistance. Changes in the 3'-5' domain emerged earlier than in the polymerase domain when viruses acquired a combination of mutations. Our study highlights the importance of poxvirus DNA polymerase residues 314, 613, 684, 688, and 851, previously linked to drug resistance, and identified several novel mutations in the 3'-5' exonuclease domain (M313I, F354L, D480Y) and in the DNA polymerase domain (A632T, T831I, E856K, L924F) associated with different drug-susceptibility profiles. Furthermore, a combination of mutations resulted in complex patterns of cross-resistance. Modeling of the VACV DNA polymerase bearing the newly described mutations was performed to understand the effects of these mutations on the structure of the viral enzyme. We demonstrated the emergence of drug-resistant DNA polymerase mutations in complex patterns to be considered in case such mutations should eventually arise in the clinic.

• Klíčová slova
• DNA polymerase, cidofovir, drug resistance, nucleotide analogues, phosphonoacetic acid, vaccinia virus,
• Publikační typ
• časopisecké články MeSH

Synthesis of the major DNA-binding protein (ICP8) was investigated in primary rabbit kidney (RK) and Vero cells infected with the syncytial (syn) strain HSZP or with the non-syn strain KOS of herpes simplex virus type 1 (HSV-1). Results showed the following: 1. In contrast to strain KOS, the rate of viral polypeptide synthesis was accelerated in Vero cells infected with strain HSZP. The ICP8 could be detected in the nuclei of cells by one hour post-infection (hr p. i.) where it became associated with the viral DNA (DNase sensitive form). Later on (7 hr p.i.), the synthesis of viral polypeptides decreased and no further translocation of ICP8 from the cytoplasm into the nucleus was observed. 2. Strain HSZP was approx. three times more resistant to the action of phosphonoacetic acid (PAA) than strain KOS. In order to block the synthesis of HSZP gamma-2 polypeptides, a concentration of 600 micrograms PAA/ml had to be used. Under this condition, the HSZP ICP8 was translocated into the cell nucleus at later interval only (7 hr p.i.), and it was still possible to release this polypeptide from the nucleus by DNase treatment. The failure of the HSZP ICP8 to associate with the nuclear matrix (DNase resistant form) of infected cells in the absence of viral DNA replication may reflect its predominant affinity for the viral DNA which, in turn, may be responsible for the observed accelerated synthesis of the HSZP polypeptides in infected Vero cells. 3. In primary RK cells infected with strain HSZP the ICP8 did not translocate into the cell nucleus. Therefore, no gamma-2 polypeptides were synthesized.

• MeSH
• DNA vazebné proteiny MeSH
• DNA virů metabolismus   MeSH
• druhová specificita MeSH
• fibroblasty MeSH
• jaderná matrix metabolismus   MeSH
• králíci MeSH
• kultivované buňky MeSH
• kyselina fosfonoctová farmakologie   MeSH
• posttranslační úpravy proteinů účinky léků   MeSH
• regulace exprese virových genů účinky léků   MeSH
• replikace DNA MeSH
• Simplexvirus klasifikace   účinky léků   metabolismus   fyziologie   MeSH
• Vero buňky MeSH
• virové proteiny biosyntéza   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• DNA vazebné proteiny MeSH
• DNA virů MeSH
• ICP8 protein, Simplexvirus MeSH Prohlížeč
• kyselina fosfonoctová MeSH
• virové proteiny MeSH

A putative herpes simplex virus type 2 (HSV-2) growth factor (HSGF-2) was detected in a crude extract from virus infected mouse embryo cells. This factor, similar to previously described pseudorabies virus (PRV) associated growth factor (PRGF) was shown to have ability to morphologically transform non-transformed cells and to repress the transformed phenotype of transformed cells. Both activities could be neutralized with two, out of seven monoclonal antibodies directed against glycoprotein B of HSV-2. Both PRGF and HSGF-2 were detected in human embryo lung cells latently infected with PRV or HSV-2 either at 41 degrees C, or in the presence of phosphonoacetic acid. Human alpha-2 interferon, when present in medium of latently infected cells enhanced the production of both HSGF and PRGF. On the contrary, when latently infected cells were treated with 5-azacytidine the synthesis of both PRGF and HSGF-2 was completely blocked and the virus reactivated from latency replicated to higher titers than in non-treated cells. The role of PRGF and HSGF-2 in the establishment, maintenance and reactivation of latency, as well as in cellular transformation is discussed.

• MeSH
• aktivace viru MeSH
• azacytidin farmakologie   MeSH
• embryo savčí MeSH
• fenotyp MeSH
• glykoproteiny izolace a purifikace   farmakologie   fyziologie   MeSH
• HeLa buňky účinky léků   MeSH
• lidé MeSH
• monoklonální protilátky imunologie   MeSH
• myši MeSH
• nádorová transformace buněk účinky léků   MeSH
• nádorové buňky kultivované MeSH
• neutralizační testy MeSH
• prasečí herpesvirus 1 fyziologie   MeSH
• proteiny virového obalu genetika   imunologie   MeSH
• protilátky virové imunologie   MeSH
• růstové látky izolace a purifikace   farmakologie   fyziologie   MeSH
• Simplexvirus imunologie   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• azacytidin MeSH
• glycoprotein B, herpes simplex virus type 2 MeSH Prohlížeč
• glykoproteiny MeSH
• monoklonální protilátky MeSH
• proteiny virového obalu MeSH
• protilátky virové MeSH
• růstové látky MeSH