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A year of microbes

Of course there are way too many microbiology stories than I can blog about. Here are some other fascinating finds throughout the year:

A bacteria that eats plastic: Poly(ethylene terephthalate) (PET) is a component of many plastic products that have accumulated in large quantities in the environment. Researchers have isolated a bacterium that uses PET as its main energy and carbon source. This bacterium can be further developed to efficiently degrade or ferment PET waste products. (more…)

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Eaten alive from the inside: predatory bacteria kill pathogenic bacteria from the inside out

Cat and mouse, cheetah and gazelle, cougar and deer. All classic examples of predator-prey relationships that easily pop into mind. When it comes to predators, we naturally think about large animals, but what about predators in the microscopic world? In the microbial universe where cooperation and competition for nutrients, territory, and survival rapidly drive evolution, predatory bacteria have emerged. Predatory bacteria have different mechanisms of predation but generally involve attaching to and/or invading prey bacteria, killing the prey and sucking up their nutrients for its own replication. (more…)

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Solving the plasmid paradox: evolutionary advantages of multicopy plasmids

Today marks the end of 2016's World Antibiotic Awareness Week, aimed to increase awareness of antibiotic resistance and to advocate for the prudent use of these drugs.

One of the key drivers of antibiotic resistance is how rapidly bacteria acquire DNA from the environment or from other bacteria. Resistance elements are often carried on mobile elements, DNA that can move around the genome or be transferred to other genomes. The almost universal rapid assimilation of DNA by bacteria leads to the acquisition of multiple antibiotic resistance genes in a variety of bacterial species. One such example of a DNA mobile element is the plasmid, small circular DNA that replicates independently of the chromosome and can be transferred from bacterium to bacterium during cell division, transformation, and conjugation. (more…)

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Microbes in costumes trick the immune system

Halloween has finally arrived and everyone around you has been busy working on their costumes in anticipation for this glorious day of tricks and treats. Come Halloween night, you may not even recognize the faces behind the costumes. How would you tell apart friends with a sweet tooth from foes ready for some tricks?

For some bacteria, putting on costumes is an everyday event when it comes to tricking the immune system. The immune system distinguishes the body's own cells from those of invading bacteria and viruses. Since the microbe's outer membrane is usually the first thing the immune system sees, the body takes advantage of molecules found on the outer membrane┬áto generate an immune response. This seems like a wise defense mechanism but microbes have several tricks up their sleeves; they disguise themselves from the immune response by changing molecules on their outer membrane (antigenic variation) or by turning on and off expression of genes encoding for surface molecules (phase variation). (more…)

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The buzz about the honey bee microbiome

Imagine you are at a picnic on a nice sunny day. Several bees stop by buzzing around your food particularly intrigued by a bowl of fruit. Though bees may be a nuisance on this particular day, they serve an essential role in the production of much of the food we eat. They produce honey, beeswax and other products we enjoy. Bees are also crucial in pollination and without honey bees, we may not be able to enjoy fruits, nuts, and vegetables that we do today.

In the past decades, the honey bee population have declined rapidly. Between April 2015 and March 2016, beekeepers lost 44.1% of their colonies. This decline in the honey bee population could be due to many reasons including pesticides, parasites, and disease. More curiously, many colonies have fallen to colony collapse disorder (CCD), where adult worker bees die-off and surprisingly, no dead bees are found in or around the hives. The exact cause of CCD is not completely known thought many have attributed pesticides, pathogens, antibiotics, and climate change as the cause. (more…)