scholarly journals Genetic, Morphological and Antigenic Relationships between Mesonivirus Isolates from Australian Mosquitoes and Evidence for Their Horizontal Transmission

Viruses ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1159
Author(s):  
Natalee D. Newton ◽  
Agathe M. G. Colmant ◽  
Caitlin A. O’Brien ◽  
Emma Ledger ◽  
Devina Paramitha ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Monoclonal Antibodies ◽  
Nucleic Acid ◽  
Genetic Relationships ◽  
Mosquito Species ◽  
Horizontal Transmission ◽  
Antigenic Relationship ◽  
High Level ◽  
Antigenic Relationships ◽  
Prototype Virus

The Mesoniviridae are a newly assigned family of viruses in the order Nidovirales. Unlike other nidoviruses, which include the Coronaviridae, mesoniviruses are restricted to mosquito hosts and do not infect vertebrate cells. To date there is little information on the morphological and antigenic characteristics of this new group of viruses and a dearth of mesonivirus-specific research tools. In this study we determined the genetic relationships of recent Australian isolates of Alphamesonivirus 4 (Casuarina virus—CASV) and Alphamesonivirus 1 (Nam Dinh virus—NDiV), obtained from multiple mosquito species. Australian isolates of NDiV showed high-level similarity to the prototype NDiV isolate from Vietnam (99% nucleotide (nt) and amino acid (aa) identity). Isolates of CASV from Central Queensland were genetically very similar to the prototype virus from Darwin (95–96% nt and 91–92% aa identity). Electron microscopy studies demonstrated that virion diameter (≈80 nm) and spike length (≈10 nm) were similar for both viruses. Monoclonal antibodies specific to CASV and NDiV revealed a close antigenic relationship between the two viruses with 13/34 mAbs recognising both viruses. We also detected NDiV RNA on honey-soaked nucleic acid preservation cards fed on by wild mosquitoes supporting a possible mechanism of horizontal transmission between insects in nature.

Expériences sur la nature de particules trouvées dans des cas d'hépatite virale: type coronavirus, antigène Australia et particules de Dane

1974 ◽  
Vol 20 (2) ◽  
pp. 193-203 ◽  
Author(s):  
H.-W. Ackermann ◽  
G. Cherchel ◽  
J.-P. Valet ◽  
J. Matte ◽  
S. Moorjani ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Nucleic Acid ◽  
Phospholipase C ◽  
Guinea Pigs ◽  
Tween 80 ◽  
Australia Antigen ◽  
Dane Particles ◽  
Antigenic Relationships

Coronavirus-like serum particles, Australia antigen, and Dane particles were treated by various chemicals and enzymes. Results were studied by electron microscopy. Coronavirus-like particles have no nucleocapsid, no detectable nucleic acid, no antigenic relationships with Australia antigen, and seem to be phospholipoproteins. Similar particles have been found in sera of guinea pigs and in human lipoproteins, especially in the HDL and VHDL fractions. Australia antigen which appears devoid of nucleic acid, and the envelope of Dane particles are sensitive to most agents and behave as phospholipoproteins. Phospholipase C produces ring-like structures. Results differ markedly from those obtained by other workers. The capsid of Dane particles is resistant to most agents. It is separated from the envelope by Tween 80, urea, and other agents. Dane particles seem to contain nucleic acid.

Nucleic Acid Molecules Prepared by Monolayer Techniques

1972 ◽  
Vol 30 ◽  
pp. 178-179
Author(s):  
Dimitrij Lang
Keyword(s):  
Electron Microscopy ◽  
Standard Deviation ◽  
Nucleic Acid ◽  
Cytochrome C ◽  
Nucleic Acids ◽  
Contour Length ◽  
Sample Standard Deviation ◽  
Molecular Weights ◽  
Length Measurements ◽  
Protein Monolayer

The success of the protein monolayer technique for electron microscopy of individual DNA molecules is based on the prevention of aggregation and orientation of the molecules during drying on specimen grids. DNA adsorbs first to a surface-denatured, insoluble cytochrome c monolayer which is then transferred to grids, without major distortion, by touching. Fig. 1 shows three basic procedures which, modified or not, permit the study of various important properties of nucleic acids, either in concert with other methods or exclusively:1) Molecular weights relative to DNA standards as well as number distributions of molecular weights can be obtained from contour length measurements with a sample standard deviation between 1 and 4%.

Electron microscopy of the replicative events of A25 bacteriophages in group A streptococci

1972 ◽  
Vol 18 (1) ◽  
pp. 93-96 ◽  
Author(s):  
S. E. Read ◽  
R. W. Reed
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Electron Microscope ◽  
Nucleic Acid ◽  
Group A Streptococcus ◽  
Group A Streptococci ◽  
Virulent Phage ◽  
Acid Pool ◽  
Group A ◽  
A Cell

The replicative events of a virulent phage (A25) infection of a group A Streptococcus (T253) were studied using the electron microscope. The first intracellular evidence of phage replication in a cell occurred 30 min after infection with arrest of cell division and increase in the nucleic acid pool. Phage heads were evident in the nucleic acid pool of the cells 45 min after infection. Release of phages occurred by splitting of the cell wall along discrete lines. This appeared to be at sites of active wall synthesis, i.e., near the region of septum formation. Many phage components were released but relatively few complete phages indicating a relatively inefficient replicative system.

scholarly journals Infectious gastroenteritis in Norfolk Island and recovery of viruses from drinking water

1983 ◽  
Vol 91 (1) ◽  
pp. 139-146 ◽  
Author(s):  
A. M. Murphy ◽  
G. S. Grohmann ◽  
M. F. H. Sexton
Keyword(s):  
Electron Microscopy ◽  
Drinking Water ◽  
Cell Cultures ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Infectious Gastroenteritis ◽  
High Incidence ◽  
Norfolk Island ◽  
High Level

SUMMARYA high incidence of gastroenteritis in both islanders and tourists has been recorded in recent years on Norfolk Island – a popular tourist resort for Australians and New Zealanders. No bacterial cause has been found. However, electron microscopic examination of 28 faecal specimens revealed viruses associated with gastroenteritis in 21 (75%). No viruses were isolated in cell cultures. Bore water is used for drinking purposes on the island and 32 samples from 15 bores were examined for viruses by electron microscopy and culture as well as for bacterial contamination. Seven polioviruses (all type 1 vaccine strain) and adenoviruses 1 and 5 were isolated in cell cultures. In addition one rotavirus, one adenovirus and two small round viruses were detected by electron microscopy. Six of 21 samples tested showed unacceptably high levels of bacteria for drinking water. The deep ground water has apparently become contaminated with sewage effluent and is almost certainly the main cause of the high level of gastroenteritis on the island.

Definition of individual components within the cytoskeleton of Trypanosoma brucei by a library of monoclonal antibodies

1989 ◽  
Vol 93 (3) ◽  
pp. 491-500 ◽  
Author(s):  
A. Woods ◽  
T. Sherwin ◽  
R. Sasse ◽  
T.H. MacRae ◽  
A.J. Baines ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Monoclonal Antibodies ◽  
Trypanosoma Brucei ◽  
Immunofluorescence Microscopy ◽  
Complex Mixtures ◽  
Immunogold Electron Microscopy ◽  
Basal Bodies ◽  
Tubulin Isotypes ◽  
Definition Of ◽  
Attachment Zone

The detergent-insoluble T. brucei cytoskeleton consists of several morphologically distinct regions and organelles, many of which are detectable only by electron microscopy. We have produced a set of monoclonal antibodies that define each structural component of this highly ordered cytoskeleton. The monoclonal antibodies were selected by cloning of hybridomas produced from mice injected with complex mixtures of proteins of either the cytoskeleton itself or salt extracts thereof. Four antibodies define particular tubulin isotypes and locate the microtubules of the axoneme and sub-pellicular array; two antibodies recognize the flagellum attachment zone; one recognizes the paraflagellar rod and another the basal bodies. Finally, one antibody defines a detergent-insoluble component of the nucleus. The antigens detected by each monoclonal antibody have been analysed by immunofluorescence microscopy, immunogold electron microscopy and Western blotting.

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