title: Closely related Prochlorococcus genotypes show remarkably different depth distributions in two oceanic regions as revealed by in situ hybridization using 16S rRNA-targeted oligonucleotides.
abstract: An in situ hybridization method was applied to the identification of marine cyanobacteria assignable to the genus Prochlorococcus using horseradish-peroxidase-labelled 16S rRNA-targeted oligonucleotide probes in combination with tyramide signal amplification (TSA). With this method very bright signals were obtained, in contrast to hybridizations with oligonucleotides monolabelled with fluorochromes, which failed to give positive signals. Genotype-specific oligonucleotides for high light (HL)- and low light (LL)-adapted members of this genus were identified by 16S rRNA sequence analyses and their specificities confirmed in whole-cell hybridizations with cultured strains of Prochlorococcus marinus Chisholm et al., 1992, Prochlorococcus sp. and Synechococcus sp. In situ hybridization of these genotype-specific probes to field samples from stratified water bodies collected in the North Atlantic Ocean and the Red Sea allowed a rapid assessment of the abundance and spatial distribution of HL- and LL-adapted Prochlorococcus. In both oceanic regions the LL-adapted Prochlorococcus populations were localized in deeper water whereas the HL-adapted Prochlorococcus populations were not only distinct in each region but also exhibited strikingly different depth distributions, HLI being confined to shallow water in the North Atlantic, in contrast to HLII, which was present throughout the water column in the Red Sea.
authors: Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK1.
authors: Nyree J
authors: NJ
authors: West
authors: Unité de Physiologie Microbienne (CNRS URA 2172), Institut Pasteur, Paris, France3.|Max-Planck-Institut für Marine Mikrobiologie, Bremen, Germany2.
authors: Wilhelm A
authors: WA
authors: Schönhuber
authors: Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK1.
authors: Nicholas J
authors: NJ
authors: Fuller
authors: Max-Planck-Institut für Marine Mikrobiologie, Bremen, Germany2.
authors: Rudolf I
authors: RI
authors: Amann
authors: Unité de Physiologie Microbienne (CNRS URA 2172), Institut Pasteur, Paris, France3.
authors: Rosmarie
authors: R
authors: Rippka
authors: The H. Steinitz Marine Biology Laboratory, InterUniversity Institute of Eilat, Eilat, Israel4.
authors: Anton F
authors: AF
authors: Post
authors: Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK1.
authors: David J
authors: DJ
authors: Scanlan
mesh_terms: D015169:Colony Count, Microbial; D000458:Cyanobacteria / Q000145:classification* / Q000235:genetics* / Q000502:physiology; D004275:DNA, Ribosomal / Q000032:analysis; D004463:Ecology; D005434:Flow Cytometry; D020459:Genes, rRNA; D005838:Genotype; D017404:In Situ Hybridization, Fluorescence; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes / Q000235:genetics*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D012623:Seawater / Q000382:microbiology*; D017422:Sequence Analysis, DNA
chemical_list: D004275:DNA, Ribosomal; D015345:Oligonucleotide Probes; D012336:RNA, Ribosomal, 16S