by Janie — Pseudouridine, an isomer of uridine, is perhaps now most widely known for its critical role in the success of the COVID-19 mRNA vaccines. Three years ago on STC, Roberto wrote an appreciative note about this key feature of the vaccines, the N1-methylpseudouridine that acts a bit like an invisibility cloak... Read more →
How E. coli Rose to Prominence – Again, One More Addendum (2|2)
by Christoph — In the fourth and, for the time being, last episode of this 'Ecolimania' in STC, I take a look around: Do we know the diversity of the species E. coli ? And what can we learn from analyses of its pangenome ? Read more →
Through The Pilus
by Roberto — Among the many mechanisms of bacterial horizontal gene transfer, conjugation, the plasmid-mediated cell-to-cell movement of DNA, holds a special place in the heart of this old-timer E. coli geneticist. Its discovery not only allowed genetic mapping through "interrupted mating" experiments, it also opened the door to studies on the regulation of gene expression (witness the famed PaJaMo experiment). Read more →
A lesson from the comb jelly, deep-sea bacteria, and some obliging E. coli on how to thrive under pressure
by Janie — I sometimes google "Small Things Considered + a biological term of choice" looking for older articles, to see if any paradigms have changed in the span of a decade or so. In doing so, I came across this post from 2010 on plasmalogens, membrane lipids with an ether bond linking the glycerol... Read more →
How E. coli Rose to Prominence – Just One More Addendum (1|2)
by Christoph — While Roberto looked deep into the fascinating past of 'How E. coli rose to prominence' in two of his recent posts, I will take a look around ahead here in 'Just One More Addendum', and a wider look around in 'Again, One More Addendum' in an upcoming post. But that was it for the time being with this 'Ecolimania' here in STC... Read more →
Thoughts on O-Antigen Variation
by Roberto — The O-side chains of lipopolysaccharides (LPS), the outer most feature of most Gram-negative's outer membrane, are highly variable in terms of their chain length and chemical composition. In my last post, I described how the O-side chain of some bacterial strains serve as a settlement and metamorphosis cue for a marine invertebrate. My thoughts immediately took me to this question: What was the early evolutionary history of O-side chain variability? Read more →
Larval Settlement
by Roberto — Animals originate, evolve, and undergo development in a microbial world. A beautiful example of how animal development is guided by bacterial chemical cues is the metamorphosis of the bottom dwelling marine worm Hydroides elegans. Read more →
...rosette is a rosette. (3|3)
by Christoph — Among the Alphaproteobacteria, a number of species from phylogenetically distantly related orders are known for forming rosettes during growth. Despite commonalities, they all have their own peculiarities when it comes to the first cell‑cell contact(s) during "rosetting". Phaeobacter inhibens (order Rhodobacterales) cells attach to each other by their "sticky ends" at one pole... Read more →
...rosette is a rosette is a... (2|3)
by Christoph — I like to imagine that microscopists in the late 19th century who looked at water samples were happily surprised when they saw organized structures of cell clusters in the whole tangle of protists and bacteria, which they then liked to call “rosettes” because these were structures known from botany. And on closer inspection, it turned out that some of them were actually bacterial rosettes… Read more →
Rosette is a rosette is a... (1|3)
by Christoph — I dare say that every biologist was blown away when they, a decade ago or so, first saw pictures of spherical rosettes that choanoflagellates can and readily do form. Is this emergent multicellularity? Skilled microscopists had long been aware of such "rosettes" among (some) bacteria, but they never made it into the canon of bacterial shapes as they only form under certain growth conditions. Read more →