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Blochmannia is a genus of symbiotic bacteria found in carpenter ants (genus Camponotus) and their allies in the tribe Camponotini. As of 2014, Blochmannia has been discovered in the guts of over 60 species across 6 genera within the Camponotini, and is predicted to be pervasive throughout the tribe.[2][3][4][5] Blochmannia was first discovered by zoologist Friedrich Blochmann in 1887, who described "bacteria-like structures" in the ovaries and midgut of Camponotus ligniperdus in 1887.[6][7] In 2000, Candidatus Blochmannia was proposed as its own genus.[7]

Blochmannia[1]
Scientific classification
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Genus:
Candidatus Blochmannia
Like other species of the ant genus Camponotus (carpenter ants), the wood-nesting C. pennsylvanicus (shown here) possesses the obligate bacterial endosymbiont Blochmannia.

Biology

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Blochmannia bacteria are found in the midguts and ovaries of camponotine ants.[6] Within the midgut, large numbers of Blochmannia are found in bacteriocytes in the gut's epithelial layer.[8] Blochmannia is important in synthesizing essential and non essential amino acids, including tyrosine, and it helps the ant to process nitrogen.[2][9] The Blochmannia bacteria improves the ants’ nutrition and, in doing this, it is also important to the overall health of the ant colony.[9] According to the study by Zientz et al., Blochmannia improves the health of the colony of ants as a whole because worker ants use a "trophallaxis and regurgitation" system to provide the colony with food.[9] When control colonies which had Blochmannia were compared to groups where the worker ants had been given antibiotics to reduce their levels of Blochmannia , the health of the control colony was superior.[9] Zientz proposes that this superior fitness of the control ant colonies is likely due to Blochmannia improving the nutritional quality of the food that worker ants supply to the young ants, as the health effects of Blochmannia appear to decrease with the ant's maturation.[9]

Blochmannia bacteria are sensitive to heat. In one experiment, when exposed to an increased heat of 99.87 °F (37.7 °C) for 4 weeks, over 99% of Blochmannia disappeared.[10] However, even after 16 weeks exposure of this heat exposure, trace small amounts of Blochmannia survived.[10] According to researchers Fan and Wernegreen, this experiment suggests that the Blochmannia in ants could be vulnerable to the effects of global warming.[10]

Evolution

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Endosymbiosis, or when the Blochmannia bacteria and the ant hosts became bonded, occurred around 30–40 million years ago.[2] In comparing two species of Blochmannia that diverged evolutionarily around 15-20 million years ago, the extreme similarity between their genes means Blochmannia bacteria have high levels of genetic conservation.[11] The high amounts of genetic conservation suggest that the Blochmannia genes lack some recombination mechanisms.[11]


References

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  1. ^ "Candidatus Blochmannia floridanus (Candidatus Blochmannia floridanus) Genome Browser Gateway". The UCSC Genome Browser. Genome Bioinformatics Group of UC Santa Cruz.
  2. ^ a b c Feldhaar, Heike; Straka, Josef; Krischke, Markus; Berthold, Kristina; Stoll, Sascha; Mueller, Martin; Gross, Roy (2007). "Nutritional upgrading for omnivorous carpenter ants by the endosymbiont Blochmannia". BMC Biology. 5 (1): article #48. doi:10.1186/1741-7007-5-48. PMC 2206011. PMID 17971224.
  3. ^ He, Hong; Wei, Cong; Wheeler, Diana (20 April 2014). "The Gut Bacterial Communities Associated with Lab-Raised and Field-Collected Ants of Camponotus fragilis (Formicidae: Formicinae)". Current Microbiology. 69 (3): 292–302. doi:10.1007/s00284-014-0586-8. PMID 24748441. S2CID 16285607.
  4. ^ Sameshima, Shinya; Hasegawa, Eisuke; Kitade, Osamu; Minaka, Nobuhiro; Matsumoto, Tadao (1999). "Phylogenetic Comparison of Endosymbionts with Their Host Ants Based on Molecular evidence". Zoological Science. 16 (6): 993–1000. doi:10.2108/zsj.16.993. hdl:2115/66620.
  5. ^ Wernegreen, Jennifer J.; Kauppinen, Seth N.; Brady, Seán G.; Ward, Philip S. (2009-12-16). "One nutritional symbiosis begat another: Phylogenetic evidence that the ant tribe Camponotini acquired Blochmanniaby tending sap-feeding insects". BMC Evolutionary Biology. 9 (1): 292. Bibcode:2009BMCEE...9..292W. doi:10.1186/1471-2148-9-292. ISSN 1471-2148. PMC 2810300. PMID 20015388.
  6. ^ a b Sauer, Christina; Dudaczek, Dieter; Hölldobler, Bert; Gross, Roy (September 2002). "Tissue Localization of the Endosymbiotic Bacterium "Candidatus Blochmannia floridanus" in Adults and Larvae of the Carpenter Ant Camponotus floridanus". Applied and Environmental Microbiology. 68 (9): 4187–4193. Bibcode:2002ApEnM..68.4187S. doi:10.1128/AEM.68.9.4187-4193.2002. PMC 124124. PMID 12200264.
  7. ^ a b Sauer, Christina; Stackebrandt, Erko; Gadau, Jürgen; Hölldobler, Bert; Gross, Roy (2000). "Systematic relationships and cospeciation of bacterial endosymbionts and their carpenter ant host species: proposal of the new taxon Candidatus Blochmannia gen. nov". International Journal of Systematic and Evolutionary Microbiology. 50 (5): 1877–1886. doi:10.1099/00207713-50-5-1877. PMID 11034499.
  8. ^ Schröder, Doris; Deppisch, Heike; Obermayer, Malu; Krohne, Georg; Stackebrandt, Erko; Hölldobler, Bert; Goebel, Werner; Gross, Roy (August 1996). "Intracellular endosymbiotic bacteria of Camponotus species (carpenter ants): systematics, evolution and ultrastructural characterization". Molecular Microbiology. 21 (3): 479–489. doi:10.1111/j.1365-2958.1996.tb02557.x. ISSN 0950-382X. PMID 8866472.
  9. ^ a b c d e Zientz, Evelyn; Beyaert, Ivo; Gross, Roy; Feldhaar, Heike (September 2006). "Relevance of the Endosymbiosis of Blochmannia floridanus and Carpenter Ants at Different Stages of the Life Cycle of the Host". Applied and Environmental Microbiology. 72 (9): 6027–6033. Bibcode:2006ApEnM..72.6027Z. doi:10.1128/AEM.00933-06. PMC 1563639. PMID 16957225.
  10. ^ a b c Fan, Yongliang; Wernegreen, Jennifer (October 2013). "Can't Take the Heat: High Temperature Depletes Bacterial Endosymbionts of Ants". Microbial Ecology. 66 (3): 727–733. Bibcode:2013MicEc..66..727F. doi:10.1007/s00248-013-0264-6. PMC 3905736. PMID 23872930.
  11. ^ a b Degnan, Patrick; Lazarus, Adam; Wernegreen, Jennifer (August 2005). "Genome sequence of Blochmannia pennsylvanicus indicates parallel evolutionary trends among bacterial mutualists of insects". Genome Research. 15 (8): 1023–1033. doi:10.1101/gr.3771305. PMC 1182215. PMID 16077009.