From time to time, we dip into the microbiology blog by César Sánchez, Twisted Bacteria, and, with his permission, "borrow" a post such as this one about pneumonia and pneumococci, fratricide at the cellular level, and a pretty protein. And there's a video too!
"A few days ago I was happy to learn that a group of Spanish researchers — some of them from the Centro de Investigaciones Biológicas (CIB, Center for Biological Research) in Madrid, Spain — had solved the 3D structure of one of the pneumococcal lytic enzymes, called LytC. What I find remarkable is how the 3D structure elegantly explains the peculiar role that this protein plays during a process known as pneumococcal fratricide.
Some bacteria produce substances that kill surrounding microbes, and use the resulting dead bodies as a source of nutrients. Sometimes, killer and victim belong to the same species, or even they are siblings. In these cases, researchers speak of cannibalism or fratricide; although if you view microbial populations as coordinated, multicellular entities, then you may prefer to use the term programmed cell death."
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