AUTHOR=Bragina Anastasia , Maier Stefanie , Berg Christian , Müller Henry , Chobot Vladimir , Hadacek Franz , Berg Gabriele 

TITLE=Similar Diversity of Alphaproteobacteria and Nitrogenase Gene Amplicons on Two Related Sphagnum Mosses

JOURNAL=Frontiers in Microbiology

VOLUME=2

YEAR=2012

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2011.00275

DOI=10.3389/fmicb.2011.00275

ISSN=1664-302X

ABSTRACT=<p><italic>Sphagnum</italic> mosses represent a main vegetation component in ombrotrophic wetlands. They harbor a specific and diverse microbial community with essential functions for the host. To understand the extend of host specificity and impact of environment, <italic>Sphagnum fallax</italic> and <italic>Sphagnum angustifolium</italic>, two phylogenetically closely related species, which show distinct habitat preference with respect to the nutrient level, were analyzed by a multifaceted approach. Microbial fingerprints obtained by PCR-single-strand conformation polymorphism of 16S rRNA and nitrogenase-encoding (<italic>nifH</italic>) genes were highly similar for both <italic>Sphagnum</italic> species. Similarity was confirmed for colonization patterns obtained by fluorescence <italic>in situ</italic> hybridization (FISH) coupled with confocal laser scanning microscopy (CLSM): Alphaproteobacteria were the main colonizers inside the hyaline cells of <italic>Sphagnum</italic> leaves. A deeper survey of Alphaproteobacteria by 16S rRNA gene amplicon sequencing reveals a high diversity with <italic>Acidocella</italic>, <italic>Acidisphaera</italic>, <italic>Rhodopila</italic>, and <italic>Phenylobacterium</italic> as major genera for both mosses. Nitrogen fixation is an important function of <italic>Sphagnum</italic>-associated bacteria, which is fulfilled by microbial communities of Sphagna in a similar way. <italic>NifH</italic> libraries of <italic>Sphagnum</italic>-associated microbial communities were characterized by high diversity and abundance of Alphaproteobacteria but contained also diverse amplicons of other taxa, e.g., Cyanobacteria and Deltaproteobacteria. Statistically significant differences between the microbial communities of both <italic>Sphagnum</italic> species could not be discovered in any of the experimental approach. Our results show that the same close relationship, which exists between the physical, morphological, and chemical characteristics of <italic>Sphagnum</italic> mosses and the ecology and function of bog ecosystems, also connects moss plantlets with their associated bacterial communities.</p>