Biomaterial Database

Detection of enterotoxigenic Escherichia coli by dot blot hybridization with biotinylated DNA probes. 1987

H Bialkowska-Hobrzanska

A dot blot hybridization test was developed for the detection of enterotoxigenic E. coli without the use of radioisotopes. Three biotin-labeled DNA (Bio-DNA) probes corresponding to structural genes specifying heat-labile and heat-stable enterotoxins of porcine and human origin were prepared by random priming; label incorporation was significantly higher than that obtained from the use of nick translation. Bio-DNA probes were highly specific when reacted with protein- and RNA-free DNA preparations in a dot blot hybridization assay. The Bio-DNA probe, in which 40% of available thymidines were replaced by a biotin-labeled deoxyuridine, readily detected 160 pg of target DNA mixed with 6 micrograms of carrier DNA. The minimum amount of total DNA required for reliable identification of a single-copy enterotoxin gene of porcine origin within a 5,000-kilobase chromosome was found to be approximately 5 micrograms. Complete agreement among the results of Bio-DNA probe hybridization, [32P]DNA hybridization, and biological assay was demonstrated for 15 (100%) of the clinical isolates. This procedure provides a more suitable approach for the diagnosis of enterotoxigenic E. coli infections in clinical settings than the hybridization assay based on 32P-labeled DNA probes.

UI	MeSH Term	Description	Entries
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D004768	Enterotoxins	Substances that are toxic to the intestinal tract causing vomiting, diarrhea, etc.; most common enterotoxins are produced by bacteria.	Staphylococcal Enterotoxin,Enterotoxin,Staphylococcal Enterotoxins,Enterotoxin, Staphylococcal,Enterotoxins, Staphylococcal
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D005798	Genes, Bacterial	The functional hereditary units of BACTERIA.	Bacterial Gene,Bacterial Genes,Gene, Bacterial
D001427	Bacterial Toxins	Toxic substances formed in or elaborated by bacteria; they are usually proteins with high molecular weight and antigenicity; some are used as antibiotics and some to skin test for the presence of or susceptibility to certain diseases.	Bacterial Toxin,Toxins, Bacterial,Toxin, Bacterial
D001710	Biotin	A water-soluble, enzyme co-factor present in minute amounts in every living cell. It occurs mainly bound to proteins or polypeptides and is abundant in liver, kidney, pancreas, yeast, and milk.	Vitamin H,Biodermatin,Biokur,Biotin Gelfert,Biotin Hermes,Biotin-Ratiopharm,Biotine Roche,Deacura,Gabunat,Medebiotin,Medobiotin,Rombellin,Biotin Ratiopharm,Gelfert, Biotin,Hermes, Biotin,Roche, Biotine
D029968	Escherichia coli Proteins	Proteins obtained from ESCHERICHIA COLI.	E coli Proteins