by Janie — Recently I stumbled across Simon Berger's shattered glass artwork, and was reminded of RNA-seq and transcriptomics, of all things. The Swiss artist's pieces each begin with a large pane of glass. He shatters the pane, sometimes by heavy blows via hammer that generate large fragments... Read more →
Of Terms in Biology: Kymogram
by Christoph — In his presentation at a meeting in Copenhagen last year, Johan Elf showed several kymograms. No, these are not fancy versions of pie charts that everyone knows, but an intuitively accessible visualization of the localization of macromolecular complexes in living bacterial cells as they change over time. Read more →
A Solar Eclipse (and the Weight of Paper)
by Christoph — Last week I had in mind to write a short hommage to a venerable lab instrument, the flatbed chart recorder, but then the solar eclipse got in the way. More precisely, not the eclipse, but the map of the USA that went viral on social media, with the booking numbers... Read more →
Viable Counts – A Conical Approach
by Roberto — How many living cells in my culture? There are times when optical densities will not suffice, when you will want to have an accurate assay that determines viable cell counts. It's no wonder one of the first things a student of microbiology learns is the age-old concept of using "colony forming units" (aka as CFU) as a viability assay. Read more →
Go FISHing to Image Bacterial Communities
by Davide Ciccarese
Bacterial communities live in a small world where cells fill any available micron. Depending on their location and surrounding environment, they can readily respond to changes by gearing up their gene repertoire to insure their position in a densely packed biofilm. To be able to visualize this...
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Pictures Considered #61: how FtsZ-rings get shoveled to midcell in vitro
by Christoph
The last thirty years have been an "eye-opening" journey for microbial cell biologists, quite literally. I am, of course, talking about fluorescent labeling of individual cell components and the non‑invasive observation of their "behavior" in living bacterial cells. Just recently, I considered a video clip about Vibrio cholerae harpooning DNA. Now again a video clip, about...
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Pictures Considered #60: Vibrio cholerae harpooning DNA
by Christoph
Let me start with an adage: a picture is worth a thousand words. Can this also be valid for video snippets? I think so. Here you see a few seconds of a looping video showing how a cholera bacterium extends a pilus, attaches the tip to DNA in the environment, and then retracts it. Worth a thousand words? Yes, sure, but also deserving 1,000 words...
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Pictures Considered #58: Visualizing Introns
When we talk about genes and genomes today, we almost reflexively thinks of long strings of the letters G, A, T, and C. And by reading sequences, we easily detect stretches that code for proteins. We detect promoters, transcription factor binding motifs, start/stop signals for transcription, signals where introns are removed by splicing from primary transcripts... Read more →
Of Terms in Biology: DGGE
DGGE, to keep the title short, stands for denaturing gradient gel electrophoresis. You may wonder what an electrophoresis technique is doing in our 'of Terms in Biology' section, but it was once a nifty way to explore microbial diversity in environmental samples. And sometimes it still is, which struck me... Read more →
Heavy-duty Traffic, Microscale
by Christoph
Mention "flagella" and we microbiologists instantly think of these ingenious appendages that bacterial cells use to propel themselves through fluids of varying viscosities (archaea do this, too, with their archaella). We rarely think of them as an accessory to transport cargo. Yes "cargo," you read correctly, but maybe you remember...
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