Phylogenetic diversity of non-marine picocyanobacteria

CALLIERI, C.; COCI, M.; CORNO, G.; MACEK, M.; MODENUTTI, B.E.; BALSEIRO, E.G.; BERTONI, R.

FEMS MICROBIOLOGY ECOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2013 vol. 85 p. 293 - 301

0168-6496

We studied the phylogenetic diversity of nonmarine picocyanobacteria broadeningthe sequence data set with 43 new sequences of the 16S rRNA gene. Thesequences were derived from monoclonal strains isolated from four volcanichigh-altitude athalassohaline lakes in Mexico, five glacial ultraoligotrophicNorth Patagonian lakes and six Italian lakes of glacial, volcanic and morenicorigin. The new sequences fall into a number of both novel and previouslydescribed clades within the phylogenetic tree of 16S rRNA gene. The new clusterof Lake Nahuel Huapi (North Patagonia) forms a sister clade to the subalpinecluster II and the marine Synechococcus subcluster 5.2. Our finding of thenovel clade of ‘halotolerants’ close to the marine subcluster 5.3 (SynechococcusRCC307) constitutes an important demonstration that euryhaline and marinestrains affiliate closely. The intriguing results obtained shed new light on theimportance of the nonmarine halotolerants in the phylogenesis of picocyanobacteria.