March 2017

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Bacteria’s toxic addiction to DNA

For bacteria, addiction to DNA can be a life or death situation. Lose that DNA and the bacterium suffers an unfortunate toxic death.

Many bacteria easily transfer DNA amongst themselves in the forms of plasmid DNA. Plasmids are mobile genetic elements that replicate independently of the chromosome. These small circular pieces of DNA often contain genes that provide its carrier a survival advantage under specific environmental conditions. For example, if a bacterium contains a plasmid with an antibiotic resistance gene, it can survive antibiotic treatment. But, the plasmid is not beneficial to its host cell in all situations and poses a metabolic burden for the host. So why do these plasmids exist and remain in bacteria? (more…)

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Meet a microbiologist: Naomi Boxall

Naomi Boxall is not afraid to point out that the pictures of people in white lab coats with colorful vials of liquids do not show how real science is done. She’s had to take one of those pictures herself. Her time in science has led her to sample soil and water in the Western Australian Wheatbelt, participate in committees and workshops for postdocs and early career scientists, as well as organize morning teas and social events for her department.

A “typical day” does not exist for Naomi. She could be working in the lab one day to writing and supervising students the next day or even building bioreactors another day. She participates in science cafes and volunteers with an all girls science club. The only constant from day to day however, is coffee, food and a lunchtime walk. Naomi states, “what is good is that no day is the same as the one before and I enjoy that everything is varied and challenging.” (more…)

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Meet a microbe: Deinococcus radiodurans

Meet Deinococcus radiodurans, one of the world’s toughest bacterium. It’s an extremophile and one of the most radiation-resistant organisms known on Earth. This hardy little bacterium can survive over a thousand times the amount of radiation that would kill a human. Its tolerance to many harsh conditions has earned itself the name “Conan the Bacterium,” after the movie Conan the Barbarian. D. radiodurans is a spherical bacterium and four individual cells are typically stuck together forming a square shaped cluster. Aside from radiation resistance, D. radiodurans is also resistant to ultraviolet light and desiccation. (more…)

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Meet a microbiologist: Eva Garmendia

Eva Garmendia has always been interested in the small and invisible since she can remember. According to Eva, she was “[amazed] that there is a universe we couldn’t see and yet, we could study and understand it.” As an undergraduate at the University of Granada, she found genetics calling her name and spent her time outside of class in a genetics lab. During that time, she became interested in evolution. While studying abroad at Uppsala University in Sweden, she began her research in microbiology and was hooked. Eva noted that her interest was sparked by “the fact that microbes were alone ruling the earth for so long before multicellularity developed.” She completed a six-month project on the role of RNases in Salmonella Typhimurium. Eva saw how microbiology could help her study evolution citing “their power of rapid replication.” (more…)

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The underground social network between trees

When I picked up Peter Wohlleben's book The Hidden Life of Trees, I expected to read about interactions between fungi and plant life. And indeed, the fascinating relationships between these diverse life forms were discussed at great depths. Together, tree roots and fungi form the mycorrhiza which some have referred to as the Wood Wide Web. Fungi are fundamental to the underground social networks that trees use to communicate to one another, to warm others of danger, and to transport nutrients and water.

This symbiotic Wood Wide Web provides nutrients to the tree and the fungi. Trees that cooperate with fungi take in about twice as much nitrogen and phosphorus than plants that tap the soil alone. Fungi also filter out heavy metals and guard the tree against destructive bacteria or fungi. For their help, the fungi get something in return. Nearly a third of the tree's total food production is shuttled to the fungi. (more…)