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Communities of green sulfur bacteria were studied in selected marine and saline habitats on the basis of gene sequences of 16S rRNA and the Fenna- Matthews-Olson (FMO) protein. The availability of group-specific primers for both 16S rDNA and the fmoA gene, which is unique to green sulfur bacteria, has, for the first time, made it possible to analyze environmental communities of these bacteria by culture-independent methods using two independent genetic markers. Sequence results obtained with fmoA genes and with 16S rDNA were largely congruent to each other. All of the 16S rDNA and fmoA sequences from habitats of the Baltic Sea, the Mediterranean Sea, Sippewissett Salt Marsh (Massachusetts, USA), and Bad Water (Death Valley, California, USA) were found within salt-dependent phylogenetic lines of green sulfur bacteria established by pure culture studies. This strongly supports the existence of phylogenetic lineages of green sulfur bacteria specifically adapted to marine and saline environments and the exclusive occurrence of these bacteria in marine and saline habitats. The great majority of clone sequences belonged to different clusters of the Prosthecochloris genus and probably represent different species. Evidence for the occurrence of two new species of Prosthecochloris was also obtained. Different habitats were dominated by representatives from the Prosthecochloris group and different clusters or species of this genus were found either exclusively or as the clearly dominant green sulfur bacterium at different habitats. [Int Microbiol 2006; 9(4):259-266]

Communities of green sulfur bacteria were studied in selected marine and saline habitats on the basis of gene sequences of 16S rRNA and the Fenna- Matthews-Olson (FMO) protein. The availability of group-specific primers for both 16S rDNA and the fmoA gene, which is unique to green sulfur bacteria, has, for the first time, made it possible to analyze environmental communities of these bacteria by culture-independent methods using two independent genetic markers. Sequence results obtained with fmoA genes and with 16S rDNA were largely congruent to each other. All of the 16S rDNA and fmoA sequences from habitats of the Baltic Sea, the Mediterranean Sea, Sippewissett Salt Marsh (Massachusetts, USA), and Bad Water (Death Valley, California, USA) were found within salt-dependent phylogenetic lines of green sulfur bacteria established by pure culture studies. This strongly supports the existence of phylogenetic lineages of green sulfur bacteria specifically adapted to marine and saline environments and the exclusive occurrence of these bacteria in marine and saline habitats. The great majority of clone sequences belonged to different clusters of the Prosthecochloris genus and probably represent different species. Evidence for the occurrence of two new species of Prosthecochloris was also obtained. Different habitats were dominated by representatives from the Prosthecochloris group and different clusters or species of this genus were found either exclusively or as the clearly dominant green sulfur bacterium at different habitats. [Int Microbiol 2006; 9(4):259-266]

The phylogeny of green sulfur bacteria (GSB) was studied on the basis of nucleotide sequences. Primers were constructed that allowed sequence analysis of the fmoA gene and his deduced amino acid sequences (FMO). On 16S rDNA basis a primer specific for GSB was developed. The largely congruent phylogenetic relationship of 16S rDNA, fmoA and FMO sequences gives considerable support to the phylogeny of GSB. Five distinct groups of strains were recognized and supported by the comparison of GC contents and salt dependence of strains. The resulting phylogenetic grouping of the GSB does not correlate with their current taxonomic classification. The aim of the present studies were also the analysis of natural communities. The strategy involves procedures which were adapted from the methods well-tried with pure cultures. The results give considerable support that the diversity of salt dependent GSB in the investigated habitats is not substantially greater than it is represented by the pure cultures. Furthermore, the salt dependent species seem to be cosmopolitical.

The phylogeny of green sulfur bacteria was studied on the basis of gene sequences of the 16S rRNA and of the Fenna-Matthews-Olson (FMO) protein. Representative and type strains (31 strains total) of most of the known species were analyzed. On the basis of fmoA gene sequences from Chlorobium tepidum ATCC 49652T and Chlorobium limicola DSM 249T available from the EMBL database, primers were constructed that allowed sequence analysis of a major part of the fmoA gene. The largely congruent phylogenetic relationship of sequences of the fmoA gene and of 16S rDNA gives considerable support to the phylogeny of green sulfur bacteria previously suggested on the basis of 16S rDNA sequences. Distinct groups of strains were recognized on the basis of 16S rDNA and FMO sequences and supported by characteristic signature amino acids of FMO. Marine strains formed clusters separate from freshwater strains. The resulting phylogenetic grouping and relationship of the green sulfur bacteria do not correlate with their current taxonomic classification

The phylogeny of green sulfur bacteria was studied on the basis of gene sequences of the 16S rRNA and of the Fenna-Matthews-Olson (FMO) protein. Representative and type strains (31 strains total) of most of the known species were analyzed. On the basis of fmoA gene sequences from Chlorobium tepidum ATCC 49652T and Chlorobium limicola DSM 249T available from the EMBL database, primers were constructed that allowed sequence analysis of a major part of the fmoA gene. The largely congruent phylogenetic relationship of sequences of the fmoA gene and of 16S rDNA gives considerable support to the phylogeny of green sulfur bacteria previously suggested on the basis of 16S rDNA sequences. Distinct groups of strains were recognized on the basis of 16S rDNA and FMO sequences and supported by characteristic signature amino acids of FMO. Marine strains formed clusters separate from freshwater strains. The resulting phylogenetic grouping and relationship of the green sulfur bacteria do not correlate with their current taxonomic classification

The phylogeny of green sulfur bacteria (GSB) was studied on the basis of nucleotide sequences. Primers were constructed that allowed sequence analysis of the fmoA gene and his deduced amino acid sequences (FMO). On 16S rDNA basis a primer specific for GSB was developed. The largely congruent phylogenetic relationship of 16S rDNA, fmoA and FMO sequences gives considerable support to the phylogeny of GSB. Five distinct groups of strains were recognized and supported by the comparison of GC contents and salt dependence of strains. The resulting phylogenetic grouping of the GSB does not correlate with their current taxonomic classification. The aim of the present studies were also the analysis of natural communities. The strategy involves procedures which were adapted from the methods well-tried with pure cultures. The results give considerable support that the diversity of salt dependent GSB in the investigated habitats is not substantially greater than it is represented by the pure cultures. Furthermore, the salt dependent species seem to be cosmopolitical.

The phylogeny of green sulfur bacteria (GSB) was studied on the basis of nucleotide sequences. Primers were constructed that allowed sequence analysis of the fmoA gene and his deduced amino acid sequences (FMO). On 16S rDNA basis a primer specific for GSB was developed. The largely congruent phylogenetic relationship of 16S rDNA, fmoA and FMO sequences gives considerable support to the phylogeny of GSB. Five distinct groups of strains were recognized and supported by the comparison of GC contents and salt dependence of strains. The resulting phylogenetic grouping of the GSB does not correlate with their current taxonomic classification. The aim of the present studies were also the analysis of natural communities. The strategy involves procedures which were adapted from the methods well-tried with pure cultures. The results give considerable support that the diversity of salt dependent GSB in the investigated habitats is not substantially greater than it is represented by the pure cultures. Furthermore, the salt dependent species seem to be cosmopolitical.

The phylogeny of green sulfur bacteria (GSB) was studied on the basis of nucleotide sequences. Primers were constructed that allowed sequence analysis of the fmoA gene and his deduced amino acid sequences (FMO). On 16S rDNA basis a primer specific for GSB was developed. The largely congruent phylogenetic relationship of 16S rDNA, fmoA and FMO sequences gives considerable support to the phylogeny of GSB. Five distinct groups of strains were recognized and supported by the comparison of GC contents and salt dependence of strains. The resulting phylogenetic grouping of the GSB does not correlate with their current taxonomic classification. The aim of the present studies were also the analysis of natural communities. The strategy involves procedures which were adapted from the methods well-tried with pure cultures. The results give considerable support that the diversity of salt dependent GSB in the investigated habitats is not substantially greater than it is represented by the pure cultures. Furthermore, the salt dependent species seem to be cosmopolitical.

The phylogeny of green sulfur bacteria was studied on the basis of gene sequences of the 16S rRNA and of the Fenna-Matthews-Olson (FMO) protein. Representative and type strains (31 strains total) of most of the known species were analyzed. On the basis of fmoA gene sequences from Chlorobium tepidum ATCC 49652T and Chlorobium limicola DSM 249T available from the EMBL database, primers were constructed that allowed sequence analysis of a major part of the fmoA gene. The largely congruent phylogenetic relationship of sequences of the fmoA gene and of 16S rDNA gives considerable support to the phylogeny of green sulfur bacteria previously suggested on the basis of 16S rDNA sequences. Distinct groups of strains were recognized on the basis of 16S rDNA and FMO sequences and supported by characteristic signature amino acids of FMO. Marine strains formed clusters separate from freshwater strains. The resulting phylogenetic grouping and relationship of the green sulfur bacteria do not correlate with their current taxonomic classification