Detection of enterotoxigenic Escherichia coli in water by polymerase chain reaction amplification and hybridization

1994 ◽  
Vol 40 (4) ◽  
pp. 243-249 ◽  
Author(s):  
Z. Tamanai-Shacoori ◽  
A. Jolivet-Gougeon ◽  
M. Pommepuy ◽  
M. Cormier ◽  
R. R. Colwell

Enterotoxigenic Escherichia coli was studied in waste water, river water, and seawater from six locations along the west coast of Normandy by using the polymerase chain reaction (PCR) to amplify the heat labile (LT) gene. Cellular DNA was extracted from centrifugation pellets and amplified using PCR. The PCR products were detected by gel electrophoresis and confirmed by hybridization assay, using an 850 base pair HindIII DNA fragment probe from pEWD299 conjugated to digoxigenin and specific for the LT gene. Results of the PCR amplification were compared with those of GM1 enzyme-linked immunosorbent assay, latex agglutination, and colony hybridization. The PCR method was found to be more precise and less time consuming, especially when compared with methods requiring culture of isolates for enumeration of enterotoxigenic E. coli in water.Key words: enterotoxigenic Escherichia coli, PCR, environmental water, digoxigenin.

2001 ◽  
Vol 13 (4) ◽  
pp. 308-311 ◽  
Author(s):  
Jacek Osek

A multiplex polymerase chain reaction (PCR) system was developed for identification of enterotoxigenic Escherichia coli (ETEC) strains and to differentiate them from other gram negative enteric bacteria. This test simultaneously amplifies heat-labile (LTI) and heat-stable (STI and STII) toxin sequences and the E. coli-specific universal stress protein ( uspA). The specificity of the method was validated by single PCR tests performed with the reference E. coli and non- E. coli strains and with bacteria isolated from pig feces. The multiplex PCR allowed the rapid and specific identification of enterotoxin-positive E. coli and may be used as a method for direct determination of ETEC and to differentiate them from other E. coli and gram-negative enteric isolates.


Blood ◽  
1988 ◽  
Vol 71 (4) ◽  
pp. 1027-1032 ◽  
Author(s):  
DB Duggan ◽  
GD Ehrlich ◽  
FP Davey ◽  
S Kwok ◽  
J Sninsky ◽  
...  

Abstract A patient with a localized HTLV-I-associated lymphoproliferative disease that was misdiagnosed as Hodgkin's disease is presented. The patient's serum was negative for HTLV-I antibodies by enzyme-linked immunosorbent assay (ELISA), Western blot, and radioimmunoprecipitation. Tumor tissue DNA was negative for HTLV-I by Southern blotting but was positive for distinct HTLV-I sequences when subjected to DNA amplification using the polymerase chain reaction. We conclude that the clinical and pathologic diagnosis of HTLV-I-related lymphoma can be difficult and can be confused with Hodgkin's disease. Extremely sensitive molecular biological techniques may be required to establish a diagnosis of HTLV-I-induced lymphoma.


Blood ◽  
1994 ◽  
Vol 83 (6) ◽  
pp. 1626-1631 ◽  
Author(s):  
RJ Molot ◽  
TC Meeker ◽  
CT Wittwer ◽  
SL Perkins ◽  
GH Segal ◽  
...  

Abstract Flow immunophenotyping, DNA content analysis, and polymerase chain reaction (PCR) amplification for t(11;14) and t(14;18) were performed on 11 cases of typical mantle cell lymphoma (MCL), 5 cases of apparent MCL with proliferation centers (MCL-PC), and 5 cases of small lymphocytic lymphoma (SLL). Immunophenotyping showed IgM (P < .001), Ig light (P < .001), and CD20 (P < .001) expression to be more intense in MCL than in SLL. In MCL-PC, the mean intensity of IgM, Ig light chain, and CD20 expression was intermediate to the intensities observed in MCL and SLL. Furthermore, in contrast to SLL, all MCL and 4 of 5 MCL-PC cases exhibited stronger CD20 than CD19 expression. CD10 expression was not observed in any case and CD5 expression was present in all SLL and MCL-PC cases and in 9 of 11 MCL cases. DNA content analysis showed an S- phase fraction of less than 3% in all cases studied and, except for 1 MCL case, all lymphomas were DNA diploid. The t(11;14) breakpoint junctions involving the bcl-1 major translocation cluster were amplified by PCR in 4 of 11 (36%) MCL cases and in none of the MCL-PC or SLL cases. The t(14;18) involving the bcl-2 major breakpoint region was not identified by PCR in any case. We conclude that the level of expression of surface antigens and the rapid detection of t(11;14) by PCR are potentially useful for distinguishing MCL and SLL in the clinical setting. Further investigations as to the biologic relationship between MCL, MCL-PC, and SLL, and the utility of t(11;14) PCR in these lymphomas are warranted.


Sign in / Sign up

Export Citation Format

Share Document