In March 2012, inspectors from the U.S. Department of Agriculture uncovered a problem in Elgin, Texas. Beef sausage from a small family-run meat processor appeared to have been contaminated with a nasty bacterium called Listeria monocytogenes. The bug can make people sick and, in rare cases, be deadly. The processor had to recall more than a ton of sausage. It’s the kind of story that strikes terror in the hearts of other sausage peddlers, including Mike Satzow, so he uses phages to keep his small company's sausages safe to eat.
A selection of glass viruses by artist Luke Jerram (a full gallery and photographs of other sculptural work are also available directly from his site)
“Viruses have no color as they are smaller than the wavelength of light,” says Jerram, in an email. “So the artworks are created as alternative representations of viruses to the artificially colored imagery we receive through the media.” Jerram and Davidson create sketches, which they then take to the glassblowers, to see whether the intricate structures of the diseases can be replicated in glass, at approximately one million times their original size. RECENTLY
This week the FDA announced that they were approving a new kind of flu vaccine. Nestled in the articles was an odd fact: unlike traditional flu vaccines, the new kind, called Flublok, is produced by the cells of insects. This is the kind of detail that you might skim over without giving it a thought. If you did pause to ponder, you might be puzzled: how could insects possibly make a vaccine against viruses that infect humans? The answer may surprise you. To make vaccines, scientists are tapping into a battle between viruses and insects that’s raging in forests and fields and backyards all around us. It’s an important lesson in how to find new ideas in biotechnology: first, leave biologists free to explore the weirdest corners of nature they can find. [more inside]
"Why do parasites harm their hosts? Conventional wisdom holds that because parasites depend on their hosts for survival and transmission, they should evolve to become benign, yet many parasites cause harm. Theory predicts that parasites could evolve virulence (i.e., parasite-induced reductions in host fitness) by balancing the transmission benefits of parasite replication with the costs of host death. This idea has led researchers to predict how human interventions—such as vaccines—may alter virulence evolution, yet empirical support is critically lacking." Two papers demonstrate empirical evidence for related models predicting the origin of virulence: [more inside]
Provirophages and transpovirons as the diverse mobilome of giant viruses
Abstract: A distinct class of infectious agents, the virophages1 that infect giant viruses of the Mimiviridae family, has been recently described. Here we report the simultaneous discovery of a giant virus of Acanthamoeba polyphaga (Lentille virus) that contains an integrated genome2 of a virophage (Sputnik 2), and a member of a previously unknown class of mobile genetic elements3, the transpovirons4. The transpovirons are linear DNA elements of ∼7 kb [kilobases]5 that encompass six to eight protein-coding genes, two of which are homologous6 to virophage genes. Fluorescence7 in situ hybridization8 showed that the free form of the transpoviron replicates within the giant virus factory and accumulates in high copy numbers inside giant virus particles, Sputnik 2 particles, and amoeba cytoplasm. Analysis of deep-sequencing data showed that the virophage and the transpoviron can integrate9 in nearly any place in the chromosome of the giant virus host and that, although less frequently, the transpoviron can also be linked to the virophage chromosome. In addition, integrated fragments of transpoviron DNA were detected in several giant virus and Sputnik genomes. Analysis of 19 Mimivirus strains revealed three distinct transpovirons associated with three subgroups of Mimiviruses. The virophage, the transpoviron, and the previously identified self-splicing introns10 and inteins11 constitute the complex, interconnected mobilome12 of the giant viruses and are likely to substantially contribute to interviral gene transfer.[Full Text PDF] and two explanations in English [more inside]