
Blochmannia

Blochmannia is a genus of symbiotic bacteria found in carpenter ant. There are over 1000 species of these ants and, as of 2014, of the over 30 species of carpenter ant that have been investigated, all contain some form of "Blochmannia". The bacteria filled cells currently known as members of the genus "Blochmannia" were first discovered by zoologist F. Blochmann in the ovaries and midguts of insects in the 1880s. In 2000 "Candidatus Blochmannia" was proposed as its own genus.
Endosymbiosis, or when the "Blochmannia" bacteria and the ant hosts became bonded, occurred around 30–40 million years ago. 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. The high amounts of genetic conservation suggest that the "Blochmannia" genes lack some recombination mechanisms.
"Blochmannia" bacteria are found in the midguts of carpenter ants, as well as the ovaries of the female carpenter ants. "Blochmannia" is important in synthesizing essential and non essential amino acids, including tyrosine, and it helps the ant to process nitrogen. The "Blochmannia" bacteria improves the ants’ nutrition and, in doing this, it is also important to the overall health of the ant colony. 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. 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. 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.
"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. However, even after 16 weeks exposure of this heat exposure, trace small amounts of "Blochmannia" survived. According to researchers Fan and Wernegreen, this experiment suggests that the "Blochmannia" in ants could be vulnerable to the effects of global warming.