Detection of Escherichia coli Using Nucleic Acid Sequence-Based Amplification and Oligonucleotide Probes for 16S Ribosomal RNA

Abstract

The use of nucleic acid sequence-based amplification (NASBA), a continuous and isothermal method of in vitro nucleic acid amplification, was investigated for the specific identification of Escherichia coli (E. coli). A set of primers was selected from a highly conserved region of the 16S rRNA sequence of E. coli sandwiching a variable sequence to perform the amplification of bacterial RNA using NASBA. A probe was identified and shown to hybridize specifically to the amplified single-stranded RNA products of all tested E. coli isolates, including enterohemorrhagic serotype O157:H7. The high sensitivity of this assay system is most likely due to the large amplification power of NASBA and the high copy number of 16S rRNA.

Keywords:

• E. coli
• Escherichia coli
• NASBA
• Nucleic acid sequence-based amplification
• Viable pathogen detection
• 16S rRNA

This article was submitted as part of a Special Memorial Issue honoring Prof. George G. Guilbault.