Summary: Discontinuous DNA complementary to 16S + 23S ribosomal RNA was synthesized by random oligonucleotide priming using reverse transcriptase. cDNA generated from native or denatured rRNA template was labelled by incorporation of either [α-P]dCTP or digoxigenin-labelled dUTP during synthesis, followed by template hydrolysis. The specific activity of the radiolabelled cDNA was 10-10 c.p.m. (μg rRNA template) with 60-92% incorporation after 5 h. The length of the reverse transcript was between 20 and 1140 nucleotides and was unaffected by exclusion of primer. The cDNA probe could detect 3 pg rRNA by quantitative slot blot. In the non-radiolabelling digoxigenin system 3 μg template gave 0·5-2·0 μg cDNA after 24 h with a length of between 100 and 1225 bases. This probe could detect 50 pg rRNA. Probes were evaluated in the comparison of biotypes by hybridization to Southern blots of restriction-endonuclease-digested total DNA. The digoxigenin-labelled probe was used to identify clinical isolates of to demonstrate its potential use in laboratories requiring high-sensitivity detection without the use of radioisotopes.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error