Meta-analysis of indigenous Frankia populations in soils from five continents. Diversity of Frankia in soil

Previous studies on indigenous Frankia populations using bioassays and subsequent sequence analyses of Frankia-specific nifH gene fragments in nodules as well as Frankia-specific nifH gene clone libraries from soils resulted in the retrieval of nifH sequences representing frankiae of clusters 1 and 3 only. We contrasted these results with dat from Frankia-specific nifH gene targeted Illumina sequencing protocol to provide a more comprehensive and accurate view on the diversity of cluster 1 and 3 frankiae in these soils. The original soil samples had been collected in October 2006, with subsamples that were kept frozen at -20°C used in this study. The soil samples had been obtained from sites in 5 continents, i.e. Africa (Rwanda), Europe (Hungary), Asia (Japan), South America (Peru), and North America (Alaska, USA)