Small Things Considered

Pictures Considered #35. The Isolation of the Inner and Outer Membrane of E. coli

by Elio | In 1968, Miura and Mizushima published the first report showing that that the inner (cytoplasmic) and outer membrane of E. coli could be separated from one another. The existence of two membranes had been surmised from thin EM sections, but being able to isolate and purify them allowed further studies, especially biochemical ones. Read more →

Pictures Considered #34. The first look at the two membranes of Gram-negatives

by Elio | In a recent "Classic Spotlight" in the Journal of Bacteriology, the editor in chief, Tom Silhavy, pointed out that the first visual proof that Gram-negative bacteria have two membranes came from work by Bladen and Mergenhagen. In their 1964 paper... Read more →

Pictures Considered #33. Viral Abundance and Diversity.

by Elio | This picture should hang as a poster in every microbiological lab that is concerned with viruses (and which one isn't, one way or another?). It shows how diverse the viruses that affect hosts of the three domains of life actually are, both in replication strategy and morphology. I confess, ... Read more →

Pictures Considered #32. A Model for DNA Segregation in 1963.

by Nanne Nanninga | The classic paper on 'The Regulation of DNA Replication in Bacteria' by Jacob et al. (1963) included a model on bacterial DNA segregation. In retrospect the model had far reaching consequences which can still be felt today. It entailed a research program that inspired many scientists. Yet, the model was not the main topic of the paper. Read more →

Pictures Considered #31. An Endosymbiont On Its Way To Becoming An Organelle?

by Elio | Inside, the freshwater ameba Paulinella chromatophora carries what may be a missing link in an endosymbiont becoming an organelle. We discussed this before in some detail. Paulinella carries within it one or two large sausage-shaped photosynthetic endosymbionts that look like cyanobacteria. This endosymbiont’s genome is a respectable... Read more →

Pictures Considered #30. Of Arms And The Fungus

by Elio | Haptoglossa mirabilis looks like a particularly vicious kind of unicellular predator. For its nefarious deeds it uses a remarkably complex structure that offhand looks like a harpoon, barb-like projections and all. With this device, it injects... Read more →

Pictures Considered #28. The χ-Form Holliday Recombination Intermediate.

by Huntington Potter | The electron micrograph pictured here shows two Eco R 1-linearized plasmid DNA molecules in the midst of un­der­go­ing genetic recombination. Since David Dressler and I published it in 1977, the photo and our accompanying diagram have been re-printed... Read more →

Pictures Considered #27. »descende, audax viator...«

by Christoph Weigel | In 2008, a team of 20 scientists lead by Dylan Chivian published their finding of a motile, spore-forming, strictly anaerobic, autotrophic bacterium of the Firmicutes family in fracture water (60°C, pH 9.3) collected at a depth of 2.8 km in the Mponeng gold mine. This mine is located... Read more →

Pictures Considered #26. Rolling-Circle Replication

by Christoph Weigel | In the late 1960s, readers of structural biology papers were frequently confronted with (and confused by) electron micrographs of heavily intertwined DNA molecules that resembled a hopelessly tangled ball of wool. They were really hard to "read" even for experts, and pictures as the one considered here were notable exceptions... Read more →

Pictures Considered #25. Getting A Ride

by Elio | A recent review article deals with the fascinating phenomenon of pathogens exiting from their host cell. Sometimes, one pathogen helps another one in transmission to the next host. In one case, a Candida albicans hypha caught in the act of fleeing... Read more →