Closely related Prochlorococcus genotypes show remarkably different depth distsributions in two oceanic regions as revealed by in situ hybridization using 16S rRNA-targeted oligonucleotides

Closely related Prochlorococcus genotypes have been shown to have remarkably different depth distsributions in the Red Sea and the North Atlantic. An in situ hybridization method was used for identification of marine cyanobacteria using horseradish-peroxidase-labelled 16S rRNA targeted oligonucleotide probes in combination with tyramid signal amplification (TSA).