Autor: |
Svenning, Mette, Eriksson, Torsten, Rasmussen, Ulla |
Předmět: |
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Zdroj: |
Archives of Microbiology; Jan2005, Vol. 183 Issue 1, p19-26, 8p |
Abstrakt: |
A phylogenetic analysis of selected symbioticNostocstrain sequences and available database 16S rDNA sequences of both symbiotic and free-living cyanobacteria was carried out using maximum likelihood and Bayesian inference techniques. Most of the symbiotic strains fell into well separated clades. One clade consisted of a mixture of symbiotic and free-living isolates. This clade includesNostocsp. strain PCC 73102, the reference strain proposed forNostoc punctiforme. A separate symbiotic clade with isolates exclusively fromGunneraspecies was also obtained, suggesting that not all symbioticNostocspecies can be assigned toN. punctiforme. Moreover, isolates fromAzolla filiculoidesand one fromGunnera dentatawere well nested within a clade comprising most of theAnabaenasequences. This result supports the affiliation of theAzollaisolates with the genusAnabaenaand shows that strains within this genus can form symbioses with additional hosts. Furthermore, these symbiotic strains produced hormogonia, thereby verifying that hormogonia formation is not absent inAnabaenaand cannot be used as a criterion to distinguish it fromNostoc. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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