scholarly journals Detection of Human and Animal Rotavirus Sequences in Drinking Water

2000 ◽  
Vol 66 (6) ◽  
pp. 2690-2692 ◽  
Author(s):  
B. Gratacap-Cavallier ◽  
O. Genoulaz ◽  
K. Brengel-Pesce ◽  
H. Soule ◽  
P. Innocenti-Francillard ◽  
...  

ABSTRACT Reverse transcription-PCR analysis of drinking water in the homes of 56 children suffering from rotaviral gastroenteritis has shown the presence of the rotavirus genome in four samples. These strains were different from human rotaviruses detected in the children's feces, as determined by sequencing of the VP7-amplified fragments—three of them of animal origin (porcine or bovine) and one of human origin.

2003 ◽  
Vol 69 (11) ◽  
pp. 6541-6549 ◽  
Author(s):  
Gilbert Thierry Lamothe ◽  
Thierry Putallaz ◽  
Han Joosten ◽  
Joey D. Marugg

ABSTRACT A seminested reverse transcription-PCR method coupled to membrane filtration was optimized to investigate the presence of norovirus (NV) RNA sequences in bottled and natural mineral waters. The recovery of viral particles by filtration varied between 28 and 45%, while the limit of detection of the overall method ranged from 6 to 95 viral particles. The assay was broadly reactive, as shown by the successful detection of 27 different viral strains representing 12 common genotypes of NVs. A total of 718 bottled and natural mineral water samples were investigated, including 640 samples of finished, spring, and line products (mostly 1 to 1.5 liters), collected from 36 different water brands of various types and from diverse geographic origins over a 2-year period. In addition, 78 samples of larger volume (10 and 400 to 500 liters) and environmental swabs were investigated. From the 1,436 analyses that were performed for the detection of NVs belonging to genogroups I and II, 34 samples (2.44%) were presumptively positive by seminested RT-PCR. However, confirmation by DNA sequence analysis revealed that all presumptive positive results were either due to nonspecific amplification or to cross-contamination. In conclusion, these results do not provide any evidence for the presence of NV genome sequences in bottled waters.


2019 ◽  
Vol 11 (3) ◽  
pp. 268-273
Author(s):  
N. El Moqri ◽  
F. El Mellouli ◽  
N. Hassou ◽  
M. Benhafid ◽  
N. Abouchoaib ◽  
...  

2017 ◽  
Vol 61 (8) ◽  
Author(s):  
Jean-Christophe Marvaud ◽  
Thierry Lambert

ABSTRACT Clostridium bolteae, which belongs to the Clostridium clostridioforme complex, is a member of the human gut microbiota. Recent analysis of seven genomes of C. bolteae revealed the presence of an arr-like gene. Among these strains, only 90A7 was found to be resistant to rifampin in the absence of alteration of RpoB. Cloning of arr-cb from 90A7 in Escherichia coli combined with directed mutagenesis demonstrated that Arr-cb was functional but that a Q127→R variant present in 90A9 and 90B3 was inactive. Quantitative reverse transcription-PCR analysis indicated that arr-cb was silent in the four remaining strains because of defective transcription. Thus, two independent mechanisms can make the probably intrinsic arr-cb gene of C. bolteae cryptic.


2004 ◽  
Vol 72 (3) ◽  
pp. 1580-1586 ◽  
Author(s):  
J. Seshu ◽  
Julie A. Boylan ◽  
Frank C. Gherardini ◽  
Jonathan T. Skare

ABSTRACT The Lyme disease spirochete, Borrelia burgdorferi, encounters many environmental signals as it cycles between the arthropod vector and mammalian hosts, including temperature, pH, and other host factors. To test the possibility that dissolved oxygen modulates gene expression in B. burgdorferi, spirochetes were exposed to differential levels of dissolved oxygen, and distinct alterations were observed at both the transcriptional and translational levels. Specifically NapA, a Dps/Dpr homologue involved in the oxidative stress response in other bacteria, was reduced when B. burgdorferi was grown under oxygen-limiting conditions. In contrast, several immunoreactive proteins were altered when tested with infection-derived sera from different hosts. Specifically, OspC, DbpA, and VlsE were synthesized at greater levels when cells were grown in limiting oxygen, whereas VraA was reduced. The levels of oxygen in the medium did not affect OspA production. Real-time reverse transcription-PCR analysis of RNA isolated from infectious isolates of strains B31 and cN40 indicated that the expression of ospC, dbpA, and vlsE increased while napA expression decreased under dissolved-oxygen-limiting conditions, whereas flaB was not affected. The reverse transcription-PCR results corroborated the immunoblot analyses and indicated that the increase in OspC, DbpA, and VlsE was due to regulation at the transcriptional level of the genes encoding these antigens. These results indicate that dissolved oxygen modulates gene expression in B. burgdorferi and imply that the redox environment may be an additional regulatory cue that spirochetes exploit to adapt to the disparate niches that they occupy in nature.


2006 ◽  
Vol 78 (5) ◽  
pp. 1546-1552 ◽  
Author(s):  
Julian L. Griffin ◽  
Cherie Blenkiron ◽  
Piia K. Valonen ◽  
Carlos Caldas ◽  
Risto A Kauppinen

2009 ◽  
Vol 53 (6) ◽  
pp. 2657-2659 ◽  
Author(s):  
Samy Figueiredo ◽  
Laurent Poirel ◽  
Jacques Croize ◽  
Christine Recule ◽  
Patrice Nordmann

ABSTRACT Two clonally related Acinetobacter baumannii isolates, A1 and A2, were obtained from the same patient. Isolate A2, selected after an imipenem-containing treatment, showed reduced susceptibility to carbapenems. This resistance pattern was related to insertion of the ISAba1 element upstream of the naturally occurring bla OXA-66 carbapenemase gene as demonstrated by sequencing, reverse transcription-PCR analysis, and inactivation of the bla OXA-66 gene.


1998 ◽  
Vol 64 (2) ◽  
pp. 569-574 ◽  
Author(s):  
Jessica M. Gettemy ◽  
Biao Ma ◽  
Margaret Alic ◽  
Michael H. Gold

ABSTRACT Manganese peroxidase (MnP) gene expression in the lignin-degrading fungus Phanerochaete chrysosporium is regulated by nutrient nitrogen levels and by Mn(II), the substrate for the enzyme, as well as by heat shock and other factors. Reverse transcription-PCR (RT-PCR) of total RNA can distinguish the mRNAs of each of the three sequencedP. chrysosporium mnp genes, i.e., mnp1,mnp2, and mnp3. Quantitative RT-PCR demonstrates that each of the three transcripts is present at a similar low basal level in nitrogen-sufficient cultures, with or without Mn, and in nitrogen-limited cultures lacking Mn. However, in 5-day-old, nitrogen-limited, stationary cultures supplemented with 180 μM Mn, the levels of the mnp1 and mnp2 transcripts increased approximately 100- and 1,700-fold, respectively, over basal levels. In contrast, under these conditions, the level of themnp3 transcript did not increase significantly over the basal level. Quantitative RT-PCR of total RNA extracted from nitrogen-deficient, Mn-supplemented cultures on days 2 through 7 demonstrates that whereas the mnp1 transcript was present at relatively low levels on days 3 through 7, the mnp2transcript level peaked on day 5 and the mnp3 transcript level peaked on day 3. Comparison of total RNA extracted on day 5 from nitrogen-deficient, Mn-supplemented stationary and agitated cultures indicates that in stationary cultures, mnp2 was the major expressed mnp gene, whereas in large agitated cultures,mnp1 was the major expressed mnp gene.


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