Composition and temporal dynamics of planktonic archaeal assemblages from anaerobic sulfurous environments studied by 16S rDNA denaturing gradient gel electrophoresis and sequencing

摘要: The planktonic archaeal assemblages of several anaerobic, sulfide-rich, aquatic envi- ronments were analyzed in space and time by PCR-denaturing gradient gel electrophoresis sequencing 16S rRNA gene fragments. systems sampled different years between 1992 1998. PCR products obtained directly from the original DNA without previous nested amplification yielded successful fingerprints with mostly sharp bands gel. Nineteen sam- ples anaerobic hypolimnia 8 lakes 1 coastal lagoon NE Spain, Mallorca Switzerland compared a temporal survey was carried out one (Lake Vilar). Between 4 14 well-defined appeared. All sequenced belonged to Archaea. Although most water bodies shared same climatic conditions presence sulfide, limnological parameters among them observed dif- ferent lakes. Euryarchaeota, i.e., methanogen- thermoplasma-related sequences, appeared all samples but crenarchaeota recovered only Lake Vilar. A shift predom- inant members assemblage cluster thermo- plasmales relatives took place Vilar February June. Sequences related thermoplasmales distantly cultured strains (81% similarity rDNA) clustered branches represented environmental clones, whereas sequences methanogens grouped sequence an endosymbiont ciliate. new branch freshwater euryarchaeota within relatives. Our study indicates dynamic populations column nonther- mophilic, sulfide-rich environments, further extending diversity distribution Archaea nature. community composition suggests that grow under situ conditions. If this is case, would be active players biogeochemi- cal cycles these environments.