b432bb2e-51dc-4ea2-baa8-e38ca1c3c670
Atlantic Ocean Microbiome
Diversity patterns of marine micro-plankton are an important basis for understanding the underlying driving forces and relate them to global change. Although sequencing of rRNA genes provides community composition at high resolution, it is unclear how the choice of primers affects the results. Here we re-amplified 16S rRNA genes from DNA sampled during Polarstern Cruise ANT28-5 using universal V4-V5 primers and compared the results with those obtained previously with V5-V6 bacterial primers. For validation of our data we used metagenomes from the same stations and single amplified genomes (SAGs) from the GORG database. We found that the universal V5-V6 primers retrieved SAR11 subclades with similar relative proportions as those found in the GORG database. We confirmed an inverse bell-shaped distance decay relationship, a bimodal latitudinal diversity gradient and a maximum of alpha-diversity at intermediate temperatures (15-20°C) for Bacteria in this transect across the Atlantic Ocean from 51°S to 47°N. Patterns varied with sampling depth, sequencing depth, choice of primers and abundance filtering. We discovered a clear peak of Archaea richness at intermediate temperatures. For micro-eukaryotes, no correlation of richness with temperature was found.
Diversity patterns of marine micro-plankton are an important basis for understanding the underlying driving forces and relate them to global change. Although sequencing of rRNA genes provides community composition at high resolution, it is unclear how the choice of primers affects the results. Here we re-amplified 16S rRNA genes from DNA sampled during Polarstern Cruise ANT28-5 using universal V4-V5 primers and compared the results with those obtained previously with V5-V6 bacterial primers. For validation of our data we used metagenomes from the same stations and single amplified genomes (SAGs) from the GORG database. We found that the universal V5-V6 primers retrieved SAR11 subclades with similar relative proportions as those found in the GORG database. We confirmed an inverse bell-shaped distance decay relationship, a bimodal latitudinal diversity gradient and a maximum of alpha-diversity at intermediate temperatures (15-20°C) for Bacteria in this transect across the Atlantic Ocean from 51°S to 47°N. Patterns varied with sampling depth, sequencing depth, choice of primers and abundance filtering. We discovered a clear peak of Archaea richness at intermediate temperatures. For micro-eukaryotes, no correlation of richness with temperature was found.