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G Devauchelle

Publications and source records attributed to G Devauchelle.

At least 55 records · Page 3Linked to original sources
PubMed1989

Infectivity of vesicles prepared from chilo iridescent virus inner membrane: evidence for recombination between associated DNA fragments.

Treatment of CIV particles with octylglucoside at high ionic strength leads to the solubilization of the inner viral membrane. Incubation of permissive cells (Cf124 cells) with vesicles obtained after dialysis of the detergent shows that this fraction is infectious. This infectivity, which is very low, could only be detected after two serial passages on permissive cells. This phenomenon is, however, reproducible. Isopycnic centrifugation analysis shows that some DNA cosediments with the vesicles. Extraction and purification of this DNA confirm the presence of a large DNA fragment of about 50.10(6) Da. Digestion with restriction endonucleases demonstrated that this DNA did not correspond to a particular fragment but to a population of DNA fragments of homogeneous size arising from various regions of the viral genome. Purified viral DNA was not infectious, the presence of DNA in the vesicles could not account therefore for their infectivity. Experiments of non-genetic reactivation of purified CIV DNA by UV-irradiated virus suggest that one (or several) structural component(s) of CIV particles must be involved in the first stages of the viral replication cycle. In addition, transfection of cells with large overlapping DNA fragments could generate infectious particles when the cells were superinfected with UV-irradiated virus. It can be supposed that the vesicle suspensions, which probably contain the reactivating factor, are composed of a population of vesicles which are all different in their DNA content. Infectivity of such suspensions would be the consequence of a recombination between large overlapping DNA fragments.

Aedes↗
PubMed1988

Identification of viral antigenic determinants by monoclonal antibodies directed against Chilo iridescent virus (iridovirus type 6). Brief report.

Monoclonal antibodies (McAbs) obtained against Iridovirus type 6 (CIV) were characterized by Western blotting and/or immunoprecipitation. Seven McAbs were found to be strongly reactive with viral polypeptides of molecular weights 16 K and 18 K by Western blotting. Two McAbs were directed against a complex composed of 30 K, 50 K, and 100 K polypeptides, but failed to react with either of these free polypeptides. This finding could explain the faint reactivity of these McAbs in Western blotting and immunoprecipitation. The reactivity of the other McAbs with their antigenic determinants is also discussed.

Antibodies, Monoclonal↗
PubMed1987

[Cytometric study of the effects of destruxin E on leukemic cells in mice].

The activity of destruxin E, a cryptogamic toxin isolated from the hyphomycete Metarhizium anisopliae, was studied on mouse leukemia cells (L 1210 and P 388) in culture. Besides a cytotoxic effect, a cytostatic effect (increase of diploïd cells proportion) was observed with all doses for P 388 (from 10 micrograms/ml to 0.001 microgram/ml) and to a concentration of 0.1 microgram/ml for L 1210. At the lower doses, the effect on cellular DNA content appears distinctly.

Animals↗
PubMed1986

Monoclonal antibodies against Chilo iridescent virus (iridovirus type 6). Brief report.

Mouse hybridomas producing antibodies against proteins of Chilo Iridescent Virus were established by fusions of X 63-Ag 8-653 myeloma cells with spleen cells from balb/c mice immunized with purified disrupted viral particles. Forty monoclonal antibodies to CIV proteins have been characterized. By ELISA, 4 categories of monoclonal antibodies were defined according to their ability to react with some selected viral protein fractions used as antigen. In preliminary studies, the specificity of 2 monoclonal antibodies for some viral polypeptides was determined by immunoblotting.

Animals↗
PubMed1986

[Demonstration of pectin-lyase in Bacillus subtilis].

After a screening performed on pectinolytic micro-organisms, a strain of B. subtilis was isolated. This strain has a pectic enzyme capable of beta-elimination on highly methylated pectin (degree of esterification = 85%), without the action of a pectinesterase. This activity corresponds to that of a pectin-lyase.

Bacillus subtilis↗
PubMed1985

Protein synthesis in cells infected by chilo iridescent virus (iridovirus, type 6).

Synthesis of the polypeptides induced in CIV-infected cells was studied using radiolabelled methionine in a permissive cell line of Choristoneura fumiferana. Analysis of labelled cell extracts by high resolution polyacrylamide gel electrophoresis (PAGE) revealed the sequential appearance of at least 28 structural and non-structural polypeptides in permissive conditions. This was confirmed by analysis of protein synthesis in non-permissive cell lines of Lymantria dispar, Aedes albopictus or by the use of protein, RNA and DNA synthesis inhibitors in the permissive cell line.

Animals↗
PubMed1985

Isolation of polysomes from permissive and non-permissive invertebrate cell lines infected with chilo iridescent virus.

Chilo Iridescent virus (Iridovirus type 6 or CIV) infection results in a disaggregation of the heavy polyribosomes both in permissive and non-permissive invertebrate cell lines. The integrity of the viral genome is not involved in this event, as shown by the polysome absorbance profile on sucrose gradient, prepared from cells infected with UV treated virus. Heavy polysomes reappeared in permissive infected cells during the viral replication cycle.

Aedes↗
PubMed1984

Protein Synthesis in a Lymantria dispar Cell Line Infected by Cytoplasmic Polyhedrosis Virus.

The efficiency of replication of a cytoplasmic polyhedrosis virus isolated from a member of the order Lepidoptera, Euxoa scandens, was studied in eight different lepidopterean cell lines. Lymantria dispar cells, which were found to support viral replication, more efficiently, were used to follow the kinetics of appearance of viral-specific polypeptides by a 2-h pulse with [(35)S]methionine. Five polypeptides (ca. 120,000 molecular weight [120K], 105K, 66K, 46K, and 28K) were identified as components of the polyhedral inclusion bodies, and two polypeptides (112K and 39K) were assigned as viral-particle polypeptides. All these polypeptides were present after 24 h and were still being produced 96 h after infection. The rate of synthesis of the major polyhedral polypeptide (28K) increased in the time course of infection, whereas the background of cellular polypeptides seemed to be unaffected. An indirect immunoperoxidase technique, after sodium dodecyl sulfate-polyacrylamide gel electrophoresis was blotted to a nitrocellulose membrane, showed that traces of the major polyhedral polypeptide were found from 8 h postinfection.

Journal Article↗
PubMed1983

Structural and thermodynamic investigation of the Chilo iridescent virus (Iridovirus type 6).

Structural features and thermodynamic parameters of the complete Chilo iridescent virus (Iridovirus type 6) and its constituents, isolated from the larvae of Galleria mellonella, were evaluated by means of UV spectroscopy and microcalorimetry. It can be demonstrated that the viral DNA is attached to the coat protein in a chromatin-like fashion, which is preserved after disruption of the virus by low temperature or partial digestion of the coat protein with proteinase K. At elevated temperature however the viral DNA is denaturated irreversibly. The coat protein appears to remain in its native state during the DNA transition and its own thermal denaturation profile shows its independence from the DNA denaturation.

DNA, Viral↗
PubMed1982

Lipid composition of an iridescent virus type 6 (CIV).

The Chilo Iridescent Virus (CIV) is a lipid-containing virus propagated in vitro in choristoneura fumiferana cell cultures. We have analysed the individual lipids of the viral membrane which appeared interesting in their relative amounts and mainly in the high proportion of phosphatidylinositol. This fraction represented about 27 per cent of the phospholipid extract. The lipid composition of the viral membrane was unchanged whether the virus was propagated in vivo in larvae or in vitro in invertebrate cell cultures and was clearly different from that of the hosts.

Fatty Acids↗
PubMed1981

[Replication of type 6 ridovirus in various cell lines].

The behaviour of different Invertebrate cell lines iridovirus type 6 (CIV) infection was compared. The results allow us to distinguish at least four types of cellular systems: non-permissive systems (a. albopictus), semi-permissive systems (L. dispar) and two types of permissive systems in which the viral replication cycle is complete A. aegypti (slow replication cycle) and C. fumiferana (rapid replication cycle)

Aedes↗
PubMed1980

[Visceral localization of 14C gentamicin in the rat after administration of a single dose].

When administered intravenously to Rats, 14C Gentamicin decreased very fast in all tissues, except in kidney and cartilage. Some flexures of the small intestine contained radioactive carbon, and that was evidence for the biliary elimination of a part of the aminoglycoside. In animals with water restriction, the distribution of the antibiotic in tissues was similar to the distribution in animals with free access to water.

Animals↗
PubMed1980

Inhibition of macromolecular synthesis in cells infected with an invertebrate virus (iridovirus type 6 or CIV).

Chilo Iridescent Virus (CIV), an invertebrate virus, rapidly inhibits cellular RNA, DNA and protein synthesis in permissive and non permissive vertebrate and invertebrate cell lines. The integrity of the viral genome is not required for inhibitory expression, since viral proteins solubilized from CIV by freezing and treatment with EDTA exhibit inhibitory properties similar to those of intact virions.

Aedes↗
PubMed1980

Enzyme activities associated with an invertebrate iridovirus: protein kinase activity associated with iridescent virus type 6 (chilo iridescent virus).

Iridescent virus type 6 was found to contain an endogenous protein kinase activity which can phosphorylate some viral proteins and exogenous basic proteins. The enzyme required a divalent metal ion but was not stimulated by cyclic nucleotides. Procedures which are known to solubilize the viral envelope indicated that the protein kinase was an internal component of the virion. Conditions for protein kinase activity are described.

Journal Article↗