Secret collaborations: first insight into the life of plant-associated Archaea

Description

Plants are known to harbour a wide diversity of microorganisms, such as bacteria and fungi, influencing plant nutrition, resistance to stress and fitness. Furthermore recent studies showed that actually Archaea also shape the microbiome of plants, but their ecological roles and interactions with their hosts remained mostly unclear. To get a broader insight into the structure and function of plant-associated Archaea, we compared 37 different plants of the families Pinaceae, Ericaceae, Cyperaceae, Poaceae, Hylocomiaceae, Polytrichaceae, Aulacomniaceae, Sphagnaceae, Typhaceae, Brassicaceae, Oleaceae and Amaranthaceae, in a combined approach using 16S rRNA amplicon sequencing, whole metagenome shotgun sequencing and fluorescence in situ hybridization confocal laser scanning microscopy (FISH-CLSM). First insights into the community structure, habitat preferences and functions of plant-associated Archaea were provided. The highest relative abundances of Archaea were detected in the endosphere of olive trees (Olea europaea L.), with up to 67.3% of total reads, in dwarf shrubs (Vaccinium myrthillus and V. oxycoccus, with 33.0% and 31.7% respectively), and in the rhizosphere of sugar beets (Beta vulgaris L.) with 33.0%. Across all habitats the archaeal community structure was clearly dominated by Euryarchaeota, followed by the less abundant phylum of Crenarchaeota and Thaumarchaeota, except in O. europaea, where Thaumarchaeota were predominant. Moreover, we observed signatures for putative adaptation mechanisms of Archaea on plant hosts, including those for higher chemotaxis, nutrient cycling like CO2 fixation, stress response, especially against oxidative stress, and archaeon stability. Complementary FISH-CLSM analyses showed specific colonization pattern prevail over randomized root colonization.

Period	18 Sep 2017
Held at	18th Frankfurt meeting on<br/>Genome function and gene regulation in Archaea<br/>
Event type	Conference
Location	Schmitten, Germany