scholarly journals In situ reverse transcription to detect the cbbL gene and visualize RuBisCO in chemoautotrophic nitrifying bacteria

2001 ◽  
Vol 32 (6) ◽  
pp. 388-393 ◽  
Author(s):  
C.D. Sinigalliano ◽  
D.N. Kuhn ◽  
R.D. Jones ◽  
M.A. Guerrero
2000 ◽  
Vol 41 (4-5) ◽  
pp. 301-308 ◽  
Author(s):  
N. Noda ◽  
H. Ikuta ◽  
Y. Ebie ◽  
A. Hirata ◽  
S. Tsuneda ◽  
...  

Fluorescent antibody technique by the monoclonal antibody method is very useful and helpful for the rapid quantification and in situ detection of the specific bacteria like nitrifiers in a mixed baxterial habitat such as a biofilm. In this study, twelve monoclonal antibodies against Nitrosomonas europaea (IFO14298) and sixteen against Nitrobacter winogradskyi (IFO14297) were raised from splenocytes of mice (BALB/c). It was found that these antibodies exhibited little cross reactivity against various kinds of heterotrophic bacteria. The direct cell count method using monoclonal antibodies could exactly detect and rapidly quantify N. europaea and N. winogradskyi. Moreover, the distribution of N. europaea and N. winogradskyi in a biofilm could be examined by in situ fluorescent antibody technique. It was shown that most of N. winogradskyi existed near the surface part and most of N. europaea existed at the inner part of the polyethylene glycol (PEG) gel pellet, which had entrapped activated sludge and used in a landfill leachate treatment reactor. It was suggested that this monoclonal antibody method was utilized for estimating and controlling the population of nitrifying bacteria as a quick and favorable tool.


2008 ◽  
Vol 36 (3) ◽  
pp. 540-542 ◽  
Author(s):  
Carine Barreau ◽  
Elizabeth Benson ◽  
Helen White-Cooper

Post-meiotic transcription is widespread in mammalian spermatogenesis, but is generally believed to be absent from Drosophila spermatogenesis. Genes required during meiosis, in early spermatids or later in spermiogenesis are typically transcribed in primary spermatocytes in Drosophila. Their mRNAs are then stored in the cytoplasm until the protein product is needed. Recently, using in situ hybridization, we identified 17 Drosophila genes, collectively named ‘comets’ and ‘cups’, whose mRNAs are most abundant in, and localize to the distal ends of, elongating spermatids. Using a single-cyst quantitative RT–PCR (reverse transcription–PCR) assay, we confirmed this unusual expression pattern and conclusively demonstrate the existence of post-meiotic transcription in Drosophila spermatids. We found that transcription of comets and cups occurs just before protamines can be detected in spermatid nuclei.


1989 ◽  
Vol 5 (3) ◽  
pp. 323-335 ◽  
Author(s):  
Clive Howard-Williams ◽  
F. de Esteves ◽  
J. E. Santos ◽  
M. T. Downes

ABSTRACTWe have studied a number of related processes of the nitrogen cycle in a Brazilian floodplain lake to identify the major pools and pathways over a short time period. The study was centred on the littoral zone dominated by the floating plantEichhornia azurea, which has a large epiphyte algal community of which heterocystous cyanobacteria were the major components. The water column was continuously undersaturated with oxygen although some elevated values (to 60% saturation) were recorded in the macrophyte beds in the afternoon. Marked diel temperature changes were documented. NH4-N dominated the dissolved N component in the water with maximal values (60 mg m−3) at lowest O2, concentrations early in the morning. Nitrogen fixation (acetylene reduction) of the epiphyte community showed marked diel changes with daily values of 5 mg N fixed m−2day−1(based on 3:1 C2H4:N2ratio). Macrophyte NH4-N uptake rates (in situincubations) were 93 mg N m−2day−1. The activities of nitrifying bacteria could not be detected with the nitrapyrin block on dark CO2fixation but denitrification (acetylene block technique) was recorded in the sediments when enhanced with NO-3. The major pathways of aquatic nitrogen involved macrophyte uptake and sediment release of NH4-N.


2014 ◽  
Vol 80 (7) ◽  
pp. 2120-2124 ◽  
Author(s):  
Dapeng Wang ◽  
Shuxia Xu ◽  
David Yang ◽  
Glenn M. Young ◽  
Peng Tian

ABSTRACTHuman noroviruses (HuNoVs) are the major cause of epidemic nonbacterial gastroenteritis. Although quantitative (real-time) reverse transcription-PCR (qRT-PCR) is widely used for detecting HuNoVs, it only detects the presence of viral RNA and does not indicate viral infectivity. Human blood group antigens (HBGAs) have been identified as receptors/co-receptors for both HuNoVs and Tulane virus (TV) and are crucial for viral infection. We propose that viral infectivity can be evaluated with a molecular assay based on receptor-captured viruses. In this study, we employed TV as an HuNoV surrogate to validate the HBGA-based capture qRT-PCR method against the 50% tissue culture infectious dose (TCID50) method. We employed type B HBGA on an immuno-well module to concentrate TV, followed by amplification of the captured viral genome byin situqRT-PCR. We first demonstrated that thisin situcapture qRT-PCR (ISC-qRT-PCR) method could effectively concentrate and detect TV. We then treated TV under either partial or full inactivation conditions and measured the remaining infectivity by ISC-qRT-PCR and a tissue culture-based amplification method (TCID50). We found that the ISC-qRT-PCR method could be used to evaluate virus inactivation deriving from damage to the capsid and study interactions between the capsid and viral receptor. Heat, chlorine, and ethanol treatment primarily affect the capsid structure, which in turns affects the ability of the capsid to bind to viral receptors. Inactivation of the virus by these methods could be reflected by the ISC-qRT-PCR method and confirmed by TCID50assay. However, the loss of the infectivity caused by damage to the viral genome (such as that from UV irradiation) could not be effectively reflected by this method. Despite this limitation, the ISC-qRT-PCR provides an alternative approach to determine inactivation of Tulane virus. A particular advantage of the ISC-qRT-PCR method is that it is also a faster and easier method to effectively recover and detect the viruses, as there is no need to extract viral RNA or to transfer the captured virus from magnetic beads to PCR tubes for further amplification. Therefore, ISC-qRT-PCR can be easily adapted for use in automated systems for multiple samples.


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