Humans may claim to have invented the hypodermic needle, but in fact, nature was plying them long before we came along. Through a vanishingly thin ‘needle’, certain viruses are able to infect bacteria, such as this Escherichia coli cell (large circle). The virus uses six fibres to rest on the bacterium, like a space shuttle on the moon, before piercing the surface with its tail (faded line emerging from small circle nearest bottom). Then, just as a doctor's syringe delivers its payload, the virus uses this tube to inject the unfortunate E.coli cell with its own DNA – the genetic code of life. The cell then unwittingly creates thousands more virus copies from this blueprint, which eventually burst out, killing the bacterium. Understanding this process is important because viruses that attack bacteria in this way could offer a weapon against drug-resistant strains.
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BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
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