Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A recombinant herpes simplex 1 origin binding protein, the product of the herpes UL9 gene, has been overexpressed in mammalian cells and purified to near homogeneity. The origin binding protein shows DNA-dependent nucleoside 5'-triphosphatase and DNA helicase activities in addition to its origin binding activity. The ability to hydrolyze nucleoside 5'-triphosphates is influenced strongly by the structure and sequence of the DNA cofactor. The properties of the recombinant origin binding protein are identical to those of the protein synthesized in herpes simplex 1-infected mammalian cells.
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PMID:The herpes simplex virus 1 origin binding protein: a DNA helicase. 184 32

We have identified and partially purified a DNA-dependent ATPase that is present specifically in herpes simplex virus type 1-infected Vero cells. The enzyme which has a molecular weight of approximately 440,000 differs from the comparable host enzyme in its elution from phosphocellulose columns and in its nucleoside triphosphate specificity. The partially purified DNA-dependent ATPase is also a DNA helicase that couples ATP or GTP hydrolysis to the displacement of an oligonucleotide annealed to M13 single-stranded DNA. The enzyme requires a 3' single-stranded tail on the duplex substrate, suggesting that the polarity of unwinding is 5'----3' relative to the M13 DNA. The herpes specific DNA helicase may therefore translocate on the lagging strand in the semidiscontinuous replication of the herpes virus 1 genome.
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PMID:A DNA helicase induced by herpes simplex virus type 1. 284 Jun 45

Eleven simian virus 40-transformed cell lines from 5 different species were tested for their ability to amplify integrated simian virus 40 DNA upon infection with herpes simplex virus type I or treatment with various chemical carcinogens. Four cell lines were positive only for virus-induced gene amplification and two lines were positive for both carcinogen- and virus-induced gene amplification. Individual cell lines were assayed for the presence of an intact SV40 origin of replication, the expression of a functional SV40 T-antigen, and permissivity to herpes simplex virus replication. These parameters were found to be positive in all 6 amplification-competent cell lines. The ability of herpes simplex virus to amplify SV40 DNA sequences in transformed cells is greater than that of chemical carcinogens and can be suppressed by specific inhibitors of the herpes virus-encoded DNA polymerase.
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PMID:HSV- and chemical carcinogen-induced amplification of SV40 DNA sequences in transformed cells is cell-line-dependent. 298 11

Detergents are important reagents in membrane biochemistry. Since each membrane system studied places different demands on the detergent in terms of desirous physicochemical properties, detergents new to biochemistry must continuously be sought. Ammonium perfluorooctanoate (APFO) was investigated, as representative of fluorinated surfactants, in terms of its suitability as a "biological detergent." It did not interfere with the Markwell modification of the Lowry procedure at detergent concentrations of up to 2% (w/v). Critical micellization concentration (cmc) values (0.013-0.0275 M) for this detergent were determined in a number of buffers of biological interest. It was demonstrated that the detergent can be removed by dialysis, albeit slowly. This slow removal may be particularly useful for reconstitution/crystallization studies. Solubilization studies on several membrane systems containing the proteins listed (the major protein of the membrane sector of the vacuolar H(+)-ATPase (16 kDa protein); photosystem II; equine herpes virus (EHV) envelope proteins) indicate that it is a potent solubilizing agent, likely to enhance the yield in cases where solubilization has already been demonstrated, and, in other cases, to solubilize proteins formerly recalcitrant to solubilization. The removal of APFO from solubilized 16-kDa protein by means of Extracti-Gel D resin as a means of exchanging detergents quickly and with a minimum requirement for second detergent was investigated.
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PMID:The potential of fluorinated surfactants in membrane biochemistry. 771 73

Semliki Forest virus (SFV) enters cells by receptor-mediated endocytosis, followed by acidification of endosomes by the action of the vacuolar H(+)-ATPase. Fusion of the viral and the endosomal membrane delivers the viral genome to the cytoplasm. Direct blockade of the vacuolar H(+)-ATPase by the selective inhibitor bafilomycin A1 (BFLA1) prevented the infection of cells by SFV, if the compound was present during the first minutes of infection. Attachment and penetration of virus particles were not the targets of the antibiotic. BFLA1 and the ionophore monensin potently blocked SFV infection even at low pH, indicating that acidic pH is not sufficient for SFV to deliver its genome to the cytoplasm, but the proper functioning of the H(+)-ATPase pump is necessary. Other enveloped RNA-containing viruses, such as vesicular stomatitis virus or influenza virus were also blocked by BFLA1, whereas no effect was observed with Sendai virus, which enters into cells by direct fusion with the plasma membrane. Enveloped DNA-containing viruses, such as herpes-viruses and vaccinia virus, infected the cells even when the vacuolar H(+)-ATPase was inhibited by BFLA1; similar behaviour was observed with poliovirus and adenovirus. Animal virus particles promote the internalization of proteins and other macromolecules during entry. BFLA1 blocked co-entry of the toxin alpha-sarcin when induced by SFV, but not when induced by Sendai virus. The inhibition of the enzyme responsible for acidification of endosomes by means of the potent inhibitor BFLA1 constitutes a selective and powerful tool to analyse the low-pH dependent mechanism(s) during virus entry and will aid in understanding the mechanisms and routes of entry of animal viruses into cells.
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PMID:Involvement of the vacuolar H(+)-ATPase in animal virus entry. 793 Nov 46

Rabbit cornea (control or infected with herpes virus) was studied at different time periods after the infection. The change of both ultrastructure and topochemistry of lactate dehydrogenase, adenosine triphosphatase, 5'-nucleotidase is found. The alteration of phosphohydrolase ultracytochemistry is probably due to the enzyme mechanisms which are responsible for reproduction of the herpes simplex virus. Further study of herpetic keratitis enzymology will allow better understanding of the pathogenesis and improve the treatment of herpetic keratitis.
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PMID:[Ultrastructural and ultracytochemical analysis of herpes infected cornea]. 798 38

In tailed bacteriophages and herpes viruses, the viral DNA is packaged through the portal protein channel. Channel closure is essential to prevent DNA release after packaging. Here we present the connector structure from bacteriophage SPP1 using cryo-electron microscopy and single particle analysis. The multiprotein complex comprises the portal protein gp6 and the head completion proteins gp15 and gp16. Although we show that gp6 in the connector has a fold similar to that of the isolated portal protein, we observe conformational changes in the region of gp6 exposed to the DNA-packaging ATPase and to gp15. This reorganization does not cause closure of the channel. The connector channel traverses the full height of gp6 and gp15, but it is closed by gp16 at the bottom of the complex. Gp16 acts as a valve whose closure prevents DNA leakage, while its opening is required for DNA release upon interaction of the virus with its host.
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PMID:Structure of a viral DNA gatekeeper at 10 A resolution by cryo-electron microscopy. 1262 18

HeLa cells infected with herpes simplex virus have been examined in thin sections by electron microscopy after cytochemical staining for the presence of surface enzymes splitting adenosine triphosphate. As with uninfected HeLa cultures (18), the opaque enzyme reaction product was localized at the plasma membranes of about half the cells, tending to be present where there were microvilli and absent on smooth surfaces. Where mature extracellular herpes particles were found in association with cell membranes showing the enzyme activity, they were invariably likewise stained, and conversely, those mature particles which lay close against cells without reaction product at the surface were themselves free of it. Particles found budding into cytoplasmic vacuoles were also always without opaque deposit since this was never seen at vacuolar membranes, even in cells having the activity at the surface. The enzyme reaction product thus provided a marker indicating the manner in which the particles escape from cells and mature by budding out through cellular membranes, carrying, in the process, a portion of the latter on to themselves to form the outer viral limiting membrane. In some instances, virus particles were observed with more opaque material covering them than was present at the cell membrane with which they were associated. This finding has been taken as evidence for a physiological waxing and waning of surface enzyme activity of adenosine triphosphatase type. The fine structure of the mature extracellular virus as prepared here, using glutaraldehyde fixation, is also recorded. The observations and interpretations are discussed in full.
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PMID:ELECTRON MICROSCOPE OBSERVATIONS ON THE SURFACE ADENOSINE TRIPHOSPHATASE-LIKE ENZYMES OF HELA CELLS INFECTED WITH HERPES VIRUS. 1408 60

Terminase enzymes are common to both eukaryotic and prokaryotic double-stranded DNA viruses. These enzymes possess ATPase and nuclease activities that work in concert to "package" a viral genome into an empty procapsid, and it is likely that terminase enzymes from disparate viruses utilize a common packaging mechanism. Bacteriophage lambda terminase possesses a site-specific nuclease activity, a so-called helicase activity, a DNA translocase activity, and multiple ATPase catalytic sites that function to package viral DNA. Allosteric interactions between the multiple catalytic sites have been reported. This study probes these catalytic interactions using enzyme kinetic, photoaffinity labeling, and vanadate inhibition studies. The ensemble of data forms the basis for a minimal kinetic model for lambda terminase. The model incorporates an ADP-driven conformational reorganization of the terminase subunits assembled on viral DNA, which is central to the activation of a catalytically competent packaging machine. The proposed model provides a unifying mechanism for allosteric interaction between the multiple catalytic sites of the holoenzyme and explains much of the kinetic data in the literature. Given that similar packaging mechanisms have been proposed for viruses as dissimilar as lambda and the herpes viruses, the model may find general utility in our global understanding of the enzymology of virus assembly.
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PMID:A minimal kinetic model for a viral DNA packaging machine. 1471 82

The mode of action of the cation lithium is not well known. It is at present used as a topical drug in dermatology. Lithium inhibits many enzymes: Na/K ATPase, adenylcyclase, enzymes of the prostaglandines E1 synthesis, inositol-1-phosphatase. It is active on neutrophils et T lymphocytes, explaining in part its anti-inflammatory activity. It has a dose-dependent action on levures. It has possibly a direct inhibitory activity on DNA synthesis of herpes viruses. Lithium has a good local safety. Percutaneous penetration is weak and plasma concentrations are very much lower than that observed after oral intake. Lithium has been studied in seborrhoeic dermatitis. Its efficacy was primarily observed in psychotic patients. An assay with oral lithium did not confirmed the first observations. Topical lithium was found more efficient. Topical lithium succinate associated with zinc sulfate and lithium gluconate had a greater efficacy than placebo. Comparison with topical ketoconazole showed a non inferiority of lithium gluconate. Oral lithium also showed a reduction of symptoms' duration of herpes simplex. Cutaneous side-effects of oral lithium are frequent and numerous. Some of them may be explained by a lithium pharmacological cell activity (such as psoriasis). Teratogenicity is observed in mice and rats. Drug interactions are not expected after topical application. Irritants side effects are mainly observed after topical application; they are moderate and transitory. Lithium gluconate treatment of seborrhoeic dermatitis is a bid application during at least 8 weeks. It may be used in renal insufficiency. It is not recommended in the first trimester of pregnancy.
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PMID:[Lithium]. 1510 43


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