Biomaterial Database

Comparison of PCR-based methods for typing Escherichia coli. 2003

D Jonas, and B Spitzmüller, and K Weist, and H Rüden, and F D Daschner

Institute of Environmental Medicine and Hospital Epidemiology, Freiburg University Hospital, Freiburg, Germany. djonas@IUK3.UKL.uni-freiburg.de

OBJECTIVE To establish a library typing system appropriate for studying cross-transmission of Escherichia coli. METHODS Eighteen epidemiologically unrelated isolates were genotyped by means of pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD), repetitive (rep) PCR, and fluorescent amplified fragment length polymorphism (AFLP). Fingerprints were analyzed either by Pearson correlation or, in the case of AFLP, by Dice coefficients employing the novel 'uncertain band' software tool from GelCompar II. During a nine-month period, 112 isolates taken from 93 patients hospitalized in five intensive care units were analyzed by use of the two most discriminative PCR typing methods. RESULTS Genotyping by RAPD and rep-PCR revealed insufficient discrimination. Among 18 epidemiologically unrelated strains with 17 different PFGE patterns, IS3 rep-PCR and AFLP distinguished 10 and 18 types, respectively. Comparison of the different methods for analysis of AFLP fingerprints showed that the Dice coefficients, which ignore 'uncertain bands', offered the best concordance with visual interpretation. Consecutive isolates originating from the same patient differed in less than three fragments. CONCLUSIONS AFLP analysis showed the highest discriminative capacity for PCR typing of E. coli isolates. Analysis of fingerprints employing the Dice coefficients proved the most efficient method for an automated software-based retrieval of visually indistinguishable genotypes in an AFLP fingerprint database.

UI	MeSH Term	Description	Entries
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
D015373	Bacterial Typing Techniques	Procedures for identifying types and strains of bacteria. The most frequently employed typing systems are BACTERIOPHAGE TYPING and SEROTYPING as well as bacteriocin typing and biotyping.	Bacteriocin Typing,Biotyping, Bacterial,Typing, Bacterial,Bacterial Biotyping,Bacterial Typing,Bacterial Typing Technic,Bacterial Typing Technics,Bacterial Typing Technique,Technic, Bacterial Typing,Technics, Bacterial Typing,Technique, Bacterial Typing,Techniques, Bacterial Typing,Typing Technic, Bacterial,Typing Technics, Bacterial,Typing Technique, Bacterial,Typing Techniques, Bacterial,Typing, Bacteriocin
D016133	Polymerase Chain Reaction	In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.	Anchored PCR,Inverse PCR,Nested PCR,PCR,Anchored Polymerase Chain Reaction,Inverse Polymerase Chain Reaction,Nested Polymerase Chain Reaction,PCR, Anchored,PCR, Inverse,PCR, Nested,Polymerase Chain Reactions,Reaction, Polymerase Chain,Reactions, Polymerase Chain
D016172	DNA Fingerprinting	A technique for identifying individuals of a species that is based on the uniqueness of their DNA sequence. Uniqueness is determined by identifying which combination of allelic variations occur in the individual at a statistically relevant number of different loci. In forensic studies, RESTRICTION FRAGMENT LENGTH POLYMORPHISM of multiple, highly polymorphic VNTR LOCI or MICROSATELLITE REPEAT loci are analyzed. The number of loci used for the profile depends on the ALLELE FREQUENCY in the population.	DNA Fingerprints,DNA Profiling,DNA Typing,Genetic Fingerprinting,DNA Fingerprint,DNA Fingerprintings,DNA Profilings,DNA Typings,Fingerprint, DNA,Fingerprinting, DNA,Fingerprinting, Genetic,Fingerprintings, DNA,Fingerprintings, Genetic,Fingerprints, DNA,Genetic Fingerprintings,Profiling, DNA,Typing, DNA,Typings, DNA
D019105	Random Amplified Polymorphic DNA Technique	Technique that utilizes low-stringency polymerase chain reaction (PCR) amplification with single primers of arbitrary sequence to generate strain-specific arrays of anonymous DNA fragments. RAPD technique may be used to determine taxonomic identity, assess kinship relationships, analyze mixed genome samples, and create specific probes.	RAPD Technique,RAPD-PCR,Arbitrarily Primed PCR Reaction,RAPD Technic,Random Amplified Polymorphic DNA Technic,RAPD Technics,RAPD Techniques