Ordination of <i>Vibrio</i> communities from all different transplants.

<p>Origin_Transplant site: DB->DB, DB->OW, OW->DB, OW->OW at the beginning (June in Black) and end (September in Grey) of the experiment. Shown are the first two principle coordinates from PCoA implemented in web-based UniFrac analysis.</p

Distribution of induced virulence (%) from May to October 2010.

<p>Shown are median virulence values (%) per sampling month, with an interquartile box and a 5 to 95% range. Outliers are marked by black dots.</p

Lag analyses for the correlation between diversity (Shannon Index) and mean temperature integrated over 28 days prior to the sampling event.

<p>Day 0 corresponds to the temperature measured at the sampling day representing an immediate response, while day 28 uses the mean temperature of the previous month representing a slower response to temperature shifts. Significant correlations between diversity and temperature are depicted by black triangles.</p

Temporal variation in the amount of <i>Vibrio</i> bacteria in oyster hemolymph (HL).

<p>Quantification of total <i>Vibrio</i> spp. (open circles and triangles) isolated from oyster hemolymph stemming from the four transplant groups (origin_site), i.e. DB_DB, DB_OW, OW_DB, OW_OW. Blue lines represent oysters assayed in site OW and black lines represent oysters assayed in site DB. Solid lines show oyster origin DB, while dashed lines show oyster origin OW. Water temperature is shown on the secondary y-axis (full circles, dotted line). The area shaded in grey marks the spawning period. Different letters indicate significant differences according to Tukey HSD post hoc test. Pi charts show relative proportion of <i>Vibrio</i> isolates by phylogenetic association based on 99% similarity by BLASTN analysis in each sampling month. Color codes correspond to those in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094256#pone-0094256-g002" target="_blank">Figure 2</a>.</p

Predicted probability to encounter highly pathogenic strains (i.e. induced mortality >25%) for each sampling month.

<p>Predicted probability to encounter highly pathogenic strains (i.e. induced mortality >25%) for each sampling month.</p

Phylogenetic relationships of <i>Vibrio</i> isolates sampled from oyster hemolymph.

<p>Maximum likelihood method (GTR+G+I substitution model) using concatenated sequences of three genes (16S rRNA, <i>GyrB</i>, <i>PyrH</i>) (2560 bp). Bootstrap percentages above 80% are represented by grey dots at the parent nodes. Virulence of each strain is depicted by the grey bars on the outer ring (a value of 100 corresponds to 100% mortality during inoculation experiments). Assignment to the different clades (see legend) based on 99% sequence similarity by BLASTN analysis is depicted in color on the inner ring.</p

Number of OTUs and richness estimators (Chao1 and Shannon-Wiener Index) for each sampling month (May–Oct) as well as at both sampling sites (Dietrichsenbank and Oddewatt) on the basis of 99% identity cut-off.

<p>Number of OTUs and richness estimators (Chao1 and Shannon-Wiener Index) for each sampling month (May–Oct) as well as at both sampling sites (Dietrichsenbank and Oddewatt) on the basis of 99% identity cut-off.</p

Table_4_Elevated Seawater Temperatures Decrease Microbial Diversity in the Gut of Mytilus coruscus.XLSX

The gut microbial community is critical for the host immune system, and in recent years, it has been extensively studied in vertebrates using ‘omic’ technologies. In contrast, knowledge about how the interactions between water temperature and diet affect the gut microbiota of marine invertebrates that do not thermoregulate is much less studied. In the present study, the effect of elevated seawater temperature and diet (Isochrysis zhanjiangensis and Platymonas helgolandica var. tsingtaoensis) on the gut microbial community of the commercial mussel, Mytilus coruscus, was investigated. The 16S rRNA gene sequencing was used to characterize the microbial community in M. coruscus gut. The mortality of M. coruscus exposed to a high water temperature (31°C) increased after 3 days and the diversity of the bacterial community in the gut of live M. coruscus was significantly reduced. For example, the abundance of Bacteroides (Bacteroidetes) and norank_Marinilabiaceae (Bacteroidetes) increased in the gut of M. coruscus fed I. zhanjiangensis. In M. coruscus fed P. helgolandica, the abundance of Arcobacter (Proteobacteria) and norank_Marinilabiaceae increased and the abundance of unclassified_Flavobacteriaceae (Bacteroidetes) decreased. The results obtained in the present study suggest that high temperatures favored the proliferation of opportunistic bacteria, including Bacteroides and Arcobacter, which may increase host susceptibility to disease. Microbial community composition of the gut in live M. coruscus was not impacted by the microalgal diet but it was modified in the group of mussels that died. The present study provides insight into the potential effects on the gut microbiome and mussel–bacteria interactions of rising seawater temperatures.</p

Table_6_Elevated Seawater Temperatures Decrease Microbial Diversity in the Gut of Mytilus coruscus.XLSX

<p>The gut microbial community is critical for the host immune system, and in recent years, it has been extensively studied in vertebrates using ‘omic’ technologies. In contrast, knowledge about how the interactions between water temperature and diet affect the gut microbiota of marine invertebrates that do not thermoregulate is much less studied. In the present study, the effect of elevated seawater temperature and diet (Isochrysis zhanjiangensis and Platymonas helgolandica var. tsingtaoensis) on the gut microbial community of the commercial mussel, Mytilus coruscus, was investigated. The 16S rRNA gene sequencing was used to characterize the microbial community in M. coruscus gut. The mortality of M. coruscus exposed to a high water temperature (31°C) increased after 3 days and the diversity of the bacterial community in the gut of live M. coruscus was significantly reduced. For example, the abundance of Bacteroides (Bacteroidetes) and norank_Marinilabiaceae (Bacteroidetes) increased in the gut of M. coruscus fed I. zhanjiangensis. In M. coruscus fed P. helgolandica, the abundance of Arcobacter (Proteobacteria) and norank_Marinilabiaceae increased and the abundance of unclassified_Flavobacteriaceae (Bacteroidetes) decreased. The results obtained in the present study suggest that high temperatures favored the proliferation of opportunistic bacteria, including Bacteroides and Arcobacter, which may increase host susceptibility to disease. Microbial community composition of the gut in live M. coruscus was not impacted by the microalgal diet but it was modified in the group of mussels that died. The present study provides insight into the potential effects on the gut microbiome and mussel–bacteria interactions of rising seawater temperatures.</p

Table_5_Elevated Seawater Temperatures Decrease Microbial Diversity in the Gut of Mytilus coruscus.XLSX

<p>The gut microbial community is critical for the host immune system, and in recent years, it has been extensively studied in vertebrates using ‘omic’ technologies. In contrast, knowledge about how the interactions between water temperature and diet affect the gut microbiota of marine invertebrates that do not thermoregulate is much less studied. In the present study, the effect of elevated seawater temperature and diet (Isochrysis zhanjiangensis and Platymonas helgolandica var. tsingtaoensis) on the gut microbial community of the commercial mussel, Mytilus coruscus, was investigated. The 16S rRNA gene sequencing was used to characterize the microbial community in M. coruscus gut. The mortality of M. coruscus exposed to a high water temperature (31°C) increased after 3 days and the diversity of the bacterial community in the gut of live M. coruscus was significantly reduced. For example, the abundance of Bacteroides (Bacteroidetes) and norank_Marinilabiaceae (Bacteroidetes) increased in the gut of M. coruscus fed I. zhanjiangensis. In M. coruscus fed P. helgolandica, the abundance of Arcobacter (Proteobacteria) and norank_Marinilabiaceae increased and the abundance of unclassified_Flavobacteriaceae (Bacteroidetes) decreased. The results obtained in the present study suggest that high temperatures favored the proliferation of opportunistic bacteria, including Bacteroides and Arcobacter, which may increase host susceptibility to disease. Microbial community composition of the gut in live M. coruscus was not impacted by the microalgal diet but it was modified in the group of mussels that died. The present study provides insight into the potential effects on the gut microbiome and mussel–bacteria interactions of rising seawater temperatures.</p