Double Labeling of Oligonucleotide Probes for Fluorescence In Situ Hybridization (DOPE-FISH) Improves Signal Intensity and Increases rRNA Accessibility

摘要

Fluorescence in situ hybridization (FISH) with singly labeled rRNA-targeted oligonucleotide probes is widely applied for direct identification of microbes in the environment or in clinical specimens. Here we show that a replacement of singly labeled oligonucleotide probes with 5′-, 3′-doubly labeled probes at least doubles FISH signal intensity without causing specificity problems. Furthermore, Cy3-doubly labeled probes strongly increase in situ accessibility of rRNA target sites and thus provide more flexibility for probe design.