Bayesian inference phylogenetic tree built with MrBayes employing the GTR + I + G model.

<p>Numbers indicate bootstrap values inferred after 1,000 pseudoreplicates for maximum likelihood and Bayesian posterior probabilities (values below 70.0% and 0.7 are not shown). The sequence characterized in the present work is reported in bold. Scale bar: 9 nucleotide substitutions per 100 positions. “<i>Ca</i>.” stands for “<i>Candidatus</i>”.</p

<i>In silico</i> matching of the species-specific probes Fokinia_198, Fokinia_434 and Fokinia_1250 against bacterial SSU rRNA gene sequences available from RDP (release 11, update 4) and SILVA (release 123) databases.

<p>Number of sequences in the corresponding database was 3,333,501 (RDP) or 1,756,783 (SILVA). “mism” stands for “mismatch(es)”. Reported are the number of sequences (“hits”) which theoretically hybridize with the probe allowing for the given number of mismatches.</p

Negative staining of “<i>Candidatus</i> Fokinia solitaria”.

<p>No flagella are visible. Scale bar: 0.2 μm.</p

Transmission electron microscopy images of ‘‘<i>Candidatus</i> Fokinia solitaria” in longitudinal (A, C) and transverse (B, D) sections.

<p>Black arrows point at the bacterial membranes; white arrowheads indicate fibrillar material associated to the endosymbiont (C) and host autolysosome containing the endosymbiont (D). Scale bars: 0.5 μm (A) and 0.2 μm (B, C, D).</p

Species specific recognition of the Paramecium sp. endosymbiont "Candidatus Fokinia solitaria"

The uploaded .txt-file contains the sequences of three fluorescence oligonucleotide probes specific for the SSU rRNA of the <i>Paramecium</i> sp. endosymbiont "<i>Candidatus</i> Fokinia solitaria" (Midichloriaceae, Rickettsiales) as described in Szokoli et al., accepted (PLoS ONE).<br

Species-specific <i>in situ</i> detection of “<i>Candidatus</i> Fokinia solitaria” in <i>Paramecium</i> sp. strain Rio ETE ALG 3VII at 15% formamide concentration.

<p>Merge of the signals from probes EUB338 (fluorescein-labelled, green signal) and A) species-specific probe Fokinia_434 (Cy3-labelled, red signal), B) alphaproteobacterial probe ALF1b (Cy3), C) species-specific probe Fokinia_198 (labelled with Alexa488, green signal), or D) species-specific probe Fokinia_1250 (Cy3). Stratification of the endosymbiont in section through the host cortex (A, C) and through the inner part of the host cell (B, D). “<i>Ca</i>. Fokinia solitaria” appears yellowish. Scale bars: 10 μm.</p