Archaeal and bacterial communities in deep-sea hydrogenetic ferromanganese crusts on old seamounts of the northwestern Pacific

http://www.godac.jamstec.go.jp/darwin/cruise/natsushima/nt09-02_leg2/ehttp://www.godac.jamstec.go.jp/darwin/cruise/kaiyo/ky11-02_leg1/ehttp://www.godac.jamstec.go.jp/darwin/cruise/natsushima/nt12-25/

Comparison of community structure using the weighted UniFrac method based on the 16S rRNA gene clone library data.

<p>(A) 3D plot resulting from PCoA. The percentages in the axis labels represent the percentages of variation explained by the first, second, and third principal coordinates (PC1 to PC3, respectively). (B) UPGMA (unweighted pair group method using average linkages) tree resulted from cluster analysis. * and ** indicate <i>p</i> values of <0.0001 and <0.005, respectively, determined by ANOSIM test between two groups of libraries. Data for the crusts (red), sediments (green), and seawater (blue) are shown. The rarefied number of sequences used in the calculation was 51 (i.e., the minimum number of clones for each clone library).</p

北西太平洋のマンガンクラスト表面に生息する微生物群集の比較解析

http://www.godac.jamstec.go.jp/darwin/cruise/natsushima/nt09-02_leg2/ehttp://www.godac.jamstec.go.jp/darwin/cruise/kaiyo/ky11-02_leg1/ehttp://www.godac.jamstec.go.jp/darwin/cruise/natsushima/nt12-25/ehttp://www.godac.jamstec.go.jp/darwin/cruise/kairei/kr16-01/

Archaeal and bacterial communities in deep-sea hydrogenetic ferromanganese crusts on old seamounts of the northwestern Pacific

<div><p>Deep-sea ferromanganese crusts are found ubiquitously on the surface of seamounts of the world’s oceans. Considering the wide distribution of the crusts, archaeal and bacterial communities on these crusts potentially play a significant role in biogeochemical cycling between oceans and seamounts; however little is known about phylogenetic diversity, abundance and function of the crust communities. To this end, we collected the crusts from the northwest Pacific basin and the Philippine Sea. We performed comprehensive analysis of the archaeal and bacterial communities of the collected crust samples by culture-independent molecular techniques. The distance between the sampling points was up to approximately 2,000 km. Surrounding sediments and bottom seawater were also collected as references near the sampling points of the crusts, and analyzed together. 16S rRNA gene analyses showed that the community structure of the crusts was significantly different from that of the seawater. Several members related to ammonia-oxidizers of <i>Thaumarchaeota</i> and <i>Betaproteobacteria</i> were detected in the crusts at most of all regions and depths by analyses of 16S rRNA and <i>amoA</i> genes, suggesting that the ammonia-oxidizing members are commonly present in the crusts. Although members related to the ammonia-oxidizers were also detected in the seawater, they differed from those in the crusts phylogenetically. In addition, members of uncultured groups of <i>Alpha</i>-, <i>Delta</i>- and <i>Gammaproteobacteria</i> were commonly detected in the crusts but not in the seawater. Comparison with previous studies of ferromanganese crusts and nodules suggests that the common members determined in the present study are widely distributed in the crusts and nodules on the vast seafloor. They may be key microbes for sustaining microbial ecosystems there.</p></div

OTUs of commonly detected in the ferromanganese crusts and nodules.

<p>OTUs of commonly detected in the ferromanganese crusts and nodules.</p

Phylogenetic trees of commonly detected OTUs in the crust samples.

<p>The 18 OTUs detected in the present study (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0173071#pone.0173071.t002" target="_blank">Table 2</a>) were in bold and red color. Clones recovered from crusts, nodules, and oceanic basalts were colored in blue, green, and purple, respectively. Bootstrap values (>50 of 100 replicates) are shown at the branch points. The scale bar represents 0.1 nucleotide substitutions per sequence position. The groupings for <i>Nitrosopumulaceae</i>, <i>Alpha</i>-, <i>Delta</i>-, and <i>Gammaproteobacteria</i> are based on the phylogenetic trees (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0173071#pone.0173071.s003" target="_blank">S3A–S3C and S3I Fig</a>).</p

Detection frequency of clones for each taxonomic group in the libraries of the sample types.

<p>Data for the crusts (eight libraries combined; red), sediments (six libraries combined; green), and seawater (six libraries combined; blue) are shown. Numbers in parentheses indicate the total number of clones for each category. (A) Percentages of the clones affiliated with each phylum or each class of <i>Proteobacteria</i> in the total number of analyzed clones are shown in box plots. (B) Percentages of the clones affiliated with each group in the total number of the clones affiliated in each taxon are shown in box plots. The groupings for <i>Nitrosopumulaceae</i>, <i>Alpha</i>-, <i>Delta</i>-, and <i>Gammaproteobacteria</i> are based on the phylogenetic trees (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0173071#pone.0173071.s003" target="_blank">S3A–S3C and S3I Fig</a>). The detected taxa were summarized into the four categories: [A] the taxa whose relative abundance in the crusts and/or sediments is higher than that in the seawater, [B] those whose relative abundance in the seawater is higher than that in the crusts and sediments, [C] the taxa whose relative abundance is similar among the three types of the samples, and [D] the others.</p

List of the samples used in the present study.

<p>List of the samples used in the present study.</p