Detection of enteric adenoviruses in south African waters using gene probes

1995 ◽  
Vol 31 (5-6) ◽  
pp. 345-350 ◽  
Author(s):  
B. Genthe ◽  
M. Gericke ◽  
B. Bateman ◽  
N. Mjoli ◽  
R. Kfir
Keyword(s):  
South African ◽  
Water Samples ◽  
Cellulose Fibre ◽  
Gene Probe ◽  
Viral Dna ◽  
Virus Particles ◽  
Gene Probes ◽  
Probe Hybridization ◽  
Enteric Adenoviruses ◽  
Effect Of Chlorine

Gene probes developed locally for both enteric Adenoviruses 40 and 41 were used to determine whether these viruses were present in both raw and treated waters. Approximately sixty water samples were concentrated by ultrafiltration and analysed directly for the presence of enteric adenoviruses. Three pretreatment techniques, namely sephadex columns, cellulose fibre and GenecleanTM were tested for the removal of inhibitory substances from concentrated water samples. The effect of chlorine treatment on viral detection using gene probe hybridization was also examined by exposing adenoviruses to chlorine concentrations of up to 20mg/l for 1 hour. Enteric adenoviruses were detected in up to 59% of both raw and treated waters analysed. Cellulose fibre and GenecleanTM were found to successfully remove inhibitory substances from concentrated raw waters. Viral DNA was detected after exposure to a range of chlorine concentrations indicating that the viruses detected in the treated waters may have been inactivated virus particles.

Detection of viral DNA by isothermal NASBA amplification and chemiluminescence gene probe hybridization assay in a microfluidic cartridge

2015 ◽  
Vol 70 ◽  
pp. S91-S92 ◽  
Author(s):  
F. Bonvicini ◽  
M. Mirasoli ◽  
M. Zangheri ◽  
A. Nascetti ◽  
G. De Cesare ◽  
...  
Keyword(s):  
Hybridization Assay ◽  
Gene Probe ◽  
Viral Dna ◽  
Probe Hybridization

The Occurrence of Male-Specific and Somatic Bacteriophages in Polluted South African Waters

1991 ◽  
Vol 24 (2) ◽  
pp. 251-254 ◽  
Author(s):  
R. Kfir ◽  
P. Coubrough ◽  
W. O. K. Grabow
Keyword(s):  
South African ◽  
Water Samples ◽  
Biological Treatment ◽  
Environmental Water ◽  
Environmental Water Samples ◽  
Resistance Pattern ◽  
Male Specific

The occurrence of somatic (F') and male-specific (F') coliphages and Salmonella phages in a variety of environmental water samples was studied using different bacterial hosts. The number of plaque-forming units (pfu) of the different bacteriophages were compared and their resistance pattern to a biological treatment (humus tank) and chlorination was evaluated. The presence of the bacteriophages in shellfish was also studied. The morphology of isolate bacteriophages was examined as well as the visibility of the different plaques formed. Coliphages were found to produce larger and clearer plaques than all other bacteriophages studied. In most of the environmental water samples coliphages outnumbered all other bacteriophages, with the exception of dam water in which higher levels of F' Salmonella phages were detected. The majority of the F' Salmonella phages were shown to be RNA bacteriophages.

Comparison of Cell Culture and a Poliovirus Gene Probe Assay for the Detection of Enteroviruses in Environmental Water Samples

1993 ◽  
Vol 27 (3-4) ◽  
pp. 311-314 ◽  
Author(s):  
Aaron B. Margolin ◽  
Charles P. Gerba ◽  
Kenneth J. Richardson ◽  
Jaime E. Naranjo
Keyword(s):  
Cell Culture ◽  
Activated Sludge ◽  
Water Samples ◽  
Cdna Probe ◽  
Culture Method ◽  
Tidal River ◽  
Nucleic Acid Hybridization ◽  
Treated Wastewater ◽  
Gene Probe ◽  
Naturally Occurring

Nucleic acid hybridization provides a rapid non-cell culture method for the detection of enteric viruses in water. The purpose of this work was to compare the detection of naturally occurring enteroviruses by cell culture with their detection by a poliovirus gene probe in various types of water samples. Samples of activated sludge effluent, tertiary treated wastewater (activated sludge, filtration and passage through reverse osmosis), ground water, surface water and tidal river water were processed through 1 MDS Virozorb filters to concentrate any naturally occurring virus. Viruses were eluted from the filters with pH 9.5 beef extract and reduced in volume by flocculation to 20-30 ml. These concentrates were then assayed in the BGM cell line by the cytopathogenic effects (CPE) method and by a poliovirus cDNA probe (base pairs 115-7440) labeled with 32P. A total of 233 samples were assayed in this manner. In slightly more than 93% of the samples gene probe and cell culture yielded the same results. Of these samples 36 were positive by gene probe and 28 by cell culture assay. Positive samples for gene probe were confirmed by treatment with NaOH or RNAse and then reprobed. Samples demonstrating CPE upon primary passage were confirmed positive by subsequent passage of cell lysate on a new monolayer of BGM cells. Ten samples were positive by gene probe and negative by cell culture, and 4 samples were negative by gene probe and positive by cell culture.

Digoxigenin-Labeled Probe-Based Colony Blotting Assay for Rapid Quantification of Salmonella Serovars in Seafood and Water

2012 ◽  
Vol 95 (6) ◽  
pp. 1652-1655 ◽  
Author(s):  
Rakesh Kumar ◽  
K V Lalitha
Keyword(s):  
Real Time ◽  
Water Samples ◽  
Real Time Pcr ◽  
Quantitative Detection ◽  
Gene Probe ◽  
Pcr Assay ◽  
Nylon Membrane ◽  
Rapid Enumeration ◽  
Salmonella Serovars ◽  
Labeled Probe

Abstract A non-radio-labeled probe-based detection method was developed for rapid enumeration of Salmonella in seafood and water samples. A Salmonella-specific invA gene probe was developed using a digoxigenin-based non-radio labeling assay, which was evaluated with naturally contaminated seafood and water samples. The probe-based technique was further compared with the quantitative PCR assay. The method was specific for detection of different Salmonella serovars without any nonspecific hybridization with other Salmonella-related Enterobacteriaceae. The optimum labeling efficiency was determined for the labeled probe, and 10 pg/μL probe concentration was observed to be most efficient for detection of Salmonella colonies on nylon membrane. Quantification of Salmonella in naturally contaminated seafood and water samples (n = 21) was in the range 10–102 CFU/mL. The assay successfully quantified Salmonella in spiked seafood and water samples in the presence of background flora, and the entire assay was completed within 48 h. The probe-based assay was further evaluated with real-time PCR, and results showed that the assay was comparable to real-time PCR assay. Thus, this probe-based assay can be a rapid, useful, and alternative technique for quantitative detection of Salmonella in food, feed, and water samples.

scholarly journals Enhancement of Enteric Adenovirus Cultivation by Viral Transactivator Proteins

2010 ◽  
Vol 76 (8) ◽  
pp. 2509-2516 ◽  
Author(s):  
Misoon Kim ◽  
Mi Young Lim ◽  
GwangPyo Ko
Keyword(s):  
Cell Line ◽  
Cytopathic Effect ◽  
Cell Cultivation ◽  
Promoter Regions ◽  
Viral Dna ◽  
Viral Transactivator ◽  
Food Borne ◽  
B Virus ◽  
Enteric Adenovirus ◽  
Enteric Adenoviruses

ABSTRACT Human enteric adenoviruses (HAdVs; serotypes 40 and 41) are important waterborne and food-borne pathogens. However, HAdVs are fastidious, are difficult to cultivate, and do not produce a clear cytopathic effect during cell culture within a reasonable time. Thus, we examined whether the viral transactivator proteins cytomegalovirus (CMV) IE1 and hepatitis B virus (HBV) X promoted the multiplication of HAdVs. Additionally, we constructed a new 293 cell line expressing CMV IE1 protein for cultivation assays. We analyzed the nucleic acid sequences of the promoter regions of both E1A and hexon genes, which are considered to be the most important regions for HAdV replication. Expression of either HBV X or CMV IE1 protein significantly increased the promoter activities of E1A and hexon genes of HAdVs by as much as 14-fold during cell cultivation. The promotion of HAdV expression was confirmed by increased levels of both adenoviral DNA and mRNA expression. Finally, the newly developed 293 cell line expressing CMV IE1 protein showed an increase in viral DNA ranging from 574% to 619% compared with the conventional 293 cell line. These results suggest that the newly constructed cell line could be useful for efficient cultivation and research of fastidious HAdVs.

scholarly journals A new model for the simplification of particle counting data

2012 ◽  
Vol 5 (1) ◽  
pp. 9-14
Author(s):  
M. F. Fadal ◽  
J. Haarhoff ◽  
S. Marais
Keyword(s):  
South African ◽  
Water Samples ◽  
Particle Number ◽  
Model Parameters ◽  
Particle Counting ◽  
Counting Data ◽  
Total Particle Number ◽  
Proposed Model ◽  
Total Particle ◽  
Size Interval

Abstract. This paper proposes a three-parameter mathematical model to describe the particle size distribution in a water sample. The proposed model offers some conceptual advantages over two other models reported on previously, and also provides a better fit to the particle counting data obtained from 321 water samples taken over three years at a large South African drinking water supplier. Using the data from raw water samples taken from a moderately turbid, large surface impoundment, as well as samples from the same water after treatment, typical ranges of the model parameters are presented for both raw and treated water. Once calibrated, the model allows the calculation and comparison of total particle number and volumes over any randomly selected size interval of interest.

scholarly journals Equine Infectious Anemia Virus Gag p9 Function in Early Steps of Virus Infection and Provirus Production

2005 ◽  
Vol 79 (14) ◽  
pp. 8793-8801 ◽  
Author(s):  
Sha Jin ◽  
Chaoping Chen ◽  
Ronald C. Montelaro
Keyword(s):  
Amino Acids ◽  
Equine Infectious Anemia Virus ◽  
Critical Role ◽  
Productive Infection ◽  
Viral Dna ◽  
Virus Particles ◽  
Viral Budding ◽  
Equine Infectious Anemia ◽  
Anemia Virus ◽  
First Time

ABSTRACT We have previously reported that serial truncation of the Gag p9 protein of equine infectious anemia virus (EIAV) revealed a progressive loss in replication phenotypes in transfected cells, such that a proviral mutant (E32) expressing the N-terminal 31 amino acids of p9 produced infectious virus particles similarly to parental provirus, while a proviral mutant (K30) with two fewer amino acids produced replication-defective virus particles, despite containing apparently normal levels of processed Gag and Pol proteins (C. Chen, F. Li, and R. C. Montelaro, J. Virol. 75:9762-9760, 2001). Based on these observations, we sought in the current study to identify the precise defect in K30 virion infection of permissive equine dermal (ED) cells. The results of these experiments clearly demonstrated that K30 virions entered target ED cells and produced early (minus-strand strong-stop) and late (Gag) viral DNA products as efficiently as did the replication-competent E32 mutant and parental EIAVUK viruses. However, in contrast to the replication-competent E32 mutant and parental viruses, infection with K30 mutant virus failed to produce detectable two-long-terminal-repeat DNA circles, stable integrated provirus, virus-specific Gag mRNA expression, or intracellular viral protein expression. Taken together, these data demonstrate that the K30 mutant is defective in the ability to produce sufficient nuclear viral DNA to establish a productive infection in ED cells. Thus, these observations indicate for the first time that the EIAV Gag p9 protein performs a critical role in viral DNA production and processing to provirus during EIAV infection, in addition to its previously defined role in viral budding mediated by the p9 L domain.

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