Small Things Considered

Terminal Proteins: Endless Possibilities

by Merry
Although it is far from unanimous, the great majority of phages studied so far package their genomes for intercellular space travel as linear chromosomes. Why linear rather than circular? Packaging convenience, for one thing. Many phages, including all of the tailed phages, package their chromosomes into preassembled icosahedral procapsids through a portal located... Read more →

STC downtime(s)

Unfortunately, the our website experienced a number of downtimes this week — and we're not sure when this spook will be over. We apologize and ask our readers for patience. The IT-people at ASM are doing their best to get the website online again ASAP... Read more →

The Fountain of Youth

by S. Marvin Friedman
The quest to live longer is not only the stuff of myths and legends, it is also the goal of some serious scientific research. An extensive literature in this area results from numerous experiments with primates, mice, worms, flies, and yeast. Aging is characterized by an accumulation of cellular insults caused by non-functional proteins, dysfunctional organelles, and damaged DNA... Read more →

Why CRISPR Doesn't Work in E. coli

by Elio
We received this query: »I enjoyed the article on your blog 'Six Questions About CRISPRs' by Merry Youle. I am an ex-lambdologist, having quit phage lambda in the early 70s and moved to GM-plants. There is one thing about CRISPR that I do not understand: Why did lambdologists not find CRISPR? They found phage... Read more →

Five Questions About the Foraminifera

by Elio
The Foraminifera ("forams") are among the largest and most abundant of all unicellular organisms. They can reach 20 cm in length and 18 cm in width, and the shells surrounding them are even bigger, up to 30 cm in length. They have existed in prodigious numbers that the remnants... Read more →

TWiM #91: Rats, Viruses and Bacteria

Vincent, Elio, and Michele review a study of the viruses and bacteria in commensal rats in New York City. Read more →

Fine Reading: There Is No 'Healthy' Microbiome

by Gemma and Elio
This is our first ever recommendation of an article published outside the usual scientific venues, but after all the hype we have heard about the human microbiome we were delighted to finally read a balanced account of what the research tells us and what it does not tell us. Plus… Read more →

Life on a Pig's Skin

by Sean Kearney
How frequently do microbes exchange genes when living on a host? This question has been on my mind lately. Broadly speaking, the discovery of horizontal gene transfer (HGT) revolutionized the way we think about prokaryotic evolution. No more could we think only of inheritance via vertical descent — HGT made possible the transmission of traits even between distantly related species. Read more →

A Snippet: Thioploca

by Elio
The seafloor off the coast of Chile is carpeted with bacterial mats of gigantic proportions. They cover an area as large as that of the state of Alabama. Their total weight is of the order of 100 million tons, which probably makes this the largest single species microbiome on Earth. The mats consist of huge filamentous bacteria of the genus... Read more →

On The Definition of Prokaryotes

by Nanne Nanninga
As will be argued below the present definition of a prokaryote is highly unsatisfactory. To give an example: a prokaryote is "a cell or organism lacking a nucleus and other membrane-enclose organelles, usually having its DNA in a single circular molecule". This seems a summary of the original definition of... Read more →