Limits...
Population structure of Endomicrobia in single host cells of termite gut flagellates (Trichonympha spp.).

Zheng H, Dietrich C, Thompson CL, Meuser K, Brune A - Microbes Environ. (2015)

Bottom Line: The gut microbiota of many phylogenetically lower termites is dominated by the cellulolytic flagellates of the genus Trichonympha, which are consistently associated with bacterial symbionts.We found that each host cell harbored a homogeneous population of symbionts that were specific to their respective host species, but phylogenetically distinct between each host lineage, corroborating cospeciation being caused by vertical inheritance.The experimental design of the present study also allowed for the identification of an unexpectedly large amount of tag-switching between samples, which indicated that any high-resolution analysis of microbial community structures using the pyrosequencing technique has to be interpreted with great caution.

View Article: PubMed Central - PubMed

Affiliation: Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology.

ABSTRACT
The gut microbiota of many phylogenetically lower termites is dominated by the cellulolytic flagellates of the genus Trichonympha, which are consistently associated with bacterial symbionts. In the case of Endomicrobia, an unusual lineage of endosymbionts of the Elusimicrobia phylum that is also present in other gut flagellates, previous studies have documented strict host specificity, leading to the cospeciation of "Candidatus Endomicrobium trichonymphae" with their respective flagellate hosts. However, it currently remains unclear whether one Trichonympha species is capable of harboring more than one Endomicrobia phylotype. In the present study, we selected single Trichonympha cells from the guts of Zootermopsis nevadensis and Reticulitermes santonensis and characterized their Endomicrobia populations based on internal transcribed spacer (ITS) region sequences. We found that each host cell harbored a homogeneous population of symbionts that were specific to their respective host species, but phylogenetically distinct between each host lineage, corroborating cospeciation being caused by vertical inheritance. The experimental design of the present study also allowed for the identification of an unexpectedly large amount of tag-switching between samples, which indicated that any high-resolution analysis of microbial community structures using the pyrosequencing technique has to be interpreted with great caution.

Show MeSH
(A) Maximum-likelihood tree of all Endomicrobia phylotypes (99% sequence similarity) detected in whole-genome amplification (MDA) products of all single flagellate cells. Branches shared by phylotypes from the same host species are color coded; the area of the circles indicates the relative abundance of the major phylotype in each library. Black dots indicate the position of phylotypes that originated from whole-gut samples of Zootermopsis nevadensis or Reticulitermes santonensis. (B) Pie charts indicate the relative abundance of the different Endomicrobia clusters in the whole gut samples. The colors represent the major phylotypes from selected Trichonympha cells; phylotypes from whole-gut samples are shown in grey. Phylotypes in the Pyrsonympha cluster were identified based on the sequences retrieved from selected flagellates from R. santonensis (unpublished results).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4356469&req=5

f4-30_92: (A) Maximum-likelihood tree of all Endomicrobia phylotypes (99% sequence similarity) detected in whole-genome amplification (MDA) products of all single flagellate cells. Branches shared by phylotypes from the same host species are color coded; the area of the circles indicates the relative abundance of the major phylotype in each library. Black dots indicate the position of phylotypes that originated from whole-gut samples of Zootermopsis nevadensis or Reticulitermes santonensis. (B) Pie charts indicate the relative abundance of the different Endomicrobia clusters in the whole gut samples. The colors represent the major phylotypes from selected Trichonympha cells; phylotypes from whole-gut samples are shown in grey. Phylotypes in the Pyrsonympha cluster were identified based on the sequences retrieved from selected flagellates from R. santonensis (unpublished results).

Mentions: A pyrosequencing analysis of the PCR products obtained with Endomicrobia-specific primers yielded variable read numbers per flagellate sample (after quality control, see Supplementary Fig. S2). Although the number of Endomicrobia phylotypes (99% sequence identity) obtained from all samples (17 phylotypes from 45 single host cells) was markedly larger than the number of flagellate species investigated (5 species), they all clustered more or less closely according to their respective hosts (Fig. 4A).


Population structure of Endomicrobia in single host cells of termite gut flagellates (Trichonympha spp.).

Zheng H, Dietrich C, Thompson CL, Meuser K, Brune A - Microbes Environ. (2015)

(A) Maximum-likelihood tree of all Endomicrobia phylotypes (99% sequence similarity) detected in whole-genome amplification (MDA) products of all single flagellate cells. Branches shared by phylotypes from the same host species are color coded; the area of the circles indicates the relative abundance of the major phylotype in each library. Black dots indicate the position of phylotypes that originated from whole-gut samples of Zootermopsis nevadensis or Reticulitermes santonensis. (B) Pie charts indicate the relative abundance of the different Endomicrobia clusters in the whole gut samples. The colors represent the major phylotypes from selected Trichonympha cells; phylotypes from whole-gut samples are shown in grey. Phylotypes in the Pyrsonympha cluster were identified based on the sequences retrieved from selected flagellates from R. santonensis (unpublished results).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4356469&req=5

f4-30_92: (A) Maximum-likelihood tree of all Endomicrobia phylotypes (99% sequence similarity) detected in whole-genome amplification (MDA) products of all single flagellate cells. Branches shared by phylotypes from the same host species are color coded; the area of the circles indicates the relative abundance of the major phylotype in each library. Black dots indicate the position of phylotypes that originated from whole-gut samples of Zootermopsis nevadensis or Reticulitermes santonensis. (B) Pie charts indicate the relative abundance of the different Endomicrobia clusters in the whole gut samples. The colors represent the major phylotypes from selected Trichonympha cells; phylotypes from whole-gut samples are shown in grey. Phylotypes in the Pyrsonympha cluster were identified based on the sequences retrieved from selected flagellates from R. santonensis (unpublished results).
Mentions: A pyrosequencing analysis of the PCR products obtained with Endomicrobia-specific primers yielded variable read numbers per flagellate sample (after quality control, see Supplementary Fig. S2). Although the number of Endomicrobia phylotypes (99% sequence identity) obtained from all samples (17 phylotypes from 45 single host cells) was markedly larger than the number of flagellate species investigated (5 species), they all clustered more or less closely according to their respective hosts (Fig. 4A).

Bottom Line: The gut microbiota of many phylogenetically lower termites is dominated by the cellulolytic flagellates of the genus Trichonympha, which are consistently associated with bacterial symbionts.We found that each host cell harbored a homogeneous population of symbionts that were specific to their respective host species, but phylogenetically distinct between each host lineage, corroborating cospeciation being caused by vertical inheritance.The experimental design of the present study also allowed for the identification of an unexpectedly large amount of tag-switching between samples, which indicated that any high-resolution analysis of microbial community structures using the pyrosequencing technique has to be interpreted with great caution.

View Article: PubMed Central - PubMed

Affiliation: Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology.

ABSTRACT
The gut microbiota of many phylogenetically lower termites is dominated by the cellulolytic flagellates of the genus Trichonympha, which are consistently associated with bacterial symbionts. In the case of Endomicrobia, an unusual lineage of endosymbionts of the Elusimicrobia phylum that is also present in other gut flagellates, previous studies have documented strict host specificity, leading to the cospeciation of "Candidatus Endomicrobium trichonymphae" with their respective flagellate hosts. However, it currently remains unclear whether one Trichonympha species is capable of harboring more than one Endomicrobia phylotype. In the present study, we selected single Trichonympha cells from the guts of Zootermopsis nevadensis and Reticulitermes santonensis and characterized their Endomicrobia populations based on internal transcribed spacer (ITS) region sequences. We found that each host cell harbored a homogeneous population of symbionts that were specific to their respective host species, but phylogenetically distinct between each host lineage, corroborating cospeciation being caused by vertical inheritance. The experimental design of the present study also allowed for the identification of an unexpectedly large amount of tag-switching between samples, which indicated that any high-resolution analysis of microbial community structures using the pyrosequencing technique has to be interpreted with great caution.

Show MeSH