Small Things Considered

Friend & Foe

by Christoph | In a post two month ago, I referred to 'defensive symbioses'. In a nutshell: one or more symbiotic bacteria produce a cocktail of antibiotics that provide protection of a eukaryotic host against an array of opportunistic bacterial and fungal pathogens. I introduced the term not in contrast but... Read more →

How To Turn An E. coli Into An Archaeon (Sort Of)

by Elio | Things pop up in microbiology that are truly astounding. The claim that one can partially turn a bacterium into an archaeon rates high on this list. Archaea and Bacteria belong to different main branches of the tree of life and have many distinctive biochemical and structural differences. Read more →

Even More Antibiotics In The Nursery!

by Christoph | We had learned earlier that Philanthus triangulum  beewolves – solitary digger wasps that prey on bees, hence their name – employ a "cocktail" of nine different antibiotics to protect their offspring from detrimental fungal infections. The antibiotics are produced – I repeat from the earlier post – by a bacterial symbiont, 'Candidatus Streptomyces philanthi', which the... Read more →

A Microbial Utopia: Cheese

by Nathan Jayne, Amanda Alker, and Nathalie Delherbe | Over the past decade, there have been many large scale attempts to characterize bacterial communities, from soil and ocean microbiomes to human microbiomes. There is even a collective effort to profile the Earth’s microbiome. Scientists are not only interested in knowing who is there and what they are doing, but also how... Read more →

To Not Get Lost in the Trees of Life (ToL)

by Christoph | Which picture comes to your mind if you think of the 'Tree of Life' (ToL) ? Maybe it's Ernst Haeckel's venerable oak tree ? Or is it rather Carl Woese's famous "three domains" phylogenetic tree ? Al­though highly abstract, the latter still resembles a tree with stem and branches, at least as much as does the famous "I think" sketch by Char­les Dar­win, on page 36 in his Note­book B. Read more →

Fine Reading: A Chalk Talk

by Roberto | As a means of communicating science, chalk talks can be extremely effective way to engage the audience. These days such pre­sen­ta­tions have become part and parcel of the interview process of those seeking academic jobs in the life sciences. As much as I love such chalk talks, that's not what I will discuss today. Rather, I want to bring to your attention a... Read more →

Why Be Intracellular and Be Motile?

by Elio | Why would a strict intracellular organism be motile? In the case of rickettsiae (and some not strict intracellular parasites such as the listeriae and shigellae), motility is carried out through the activity of the host's actin, apparently for the purpose of infecting adjacent cells. I am not talking about that, but rather I will consider here... Read more →

A Lakeside Tale

by Christoph Weigel | How small are bacteria ? And how big can they get as single cells ? For the lower end of the size scale, we know since the work of Jill Banfield's team that a multitude of ultra-small bacteria exist with a spherical diameters of ~0.25 µm and calculated cell vol­umes of ~0.009 µm³. Much larger are newborn cells of Escherichia coli  with a length of... Read more →

In the Beginning… there were Stromatolites

by Gillian Belk | Where can we find the first life forms on Earth? Although we do not yet know the exact microbes that managed to spin together some genetic information and make proteins, we do have evidence of life as far back at 3.5 billion years ago in what are known as stromatolites. Read more →

Old Enzymes Tell Stories

by Elio | Offhand, what can you say about the enzymes of the earliest cells? Surely, a few things pop up, for example, they were fewer in number and probably simpler than the ones we have now. They must have had fewer frills than the modern ones, which tend to have clear-cut tastes for substrates and... Read more →