Small Things Considered

The COVID-19 Virus by the Numbers

by Elio | The trio of Yinon Bar-On, Rob Phillips, and Ron Milo, here aug­men­ted by Avi Flam­holz, have done it again. In the past, they pre­sen­ted us the astound­ing num­bers for the dis­tri­bu­tion of bio­mass on this pla­net, no less. We high­light­ed this se­mi­nal con­tri­bu­tion to our un­der­stand­ing of the li­ving world... Read more →

Virus. ...simply a piece of bad news wrapped up in protein, really ?

by Christoph | In my prior post, I answered the question "are viruses alive?" with a firm: no. That was the short answer, but there is also a long answer... and it's long because it's complicated. Read more →

Virus? ...simply a piece of bad news wrapped up in protein.

by Christoph | In the middle of the first major pan­de­mic of my life­time I feel the need, as a mi­cro­bio­logist, to make oc­ca­sio­nal con­tri­bu­tions that may help in­di­vi­duals and so­cie­ty ap­proach the pan­de­mic in a rea­son­ab­ly in­form­ed way. To­day, I'd like to con­tri­bute with a small dose of 'mi­cro­bial li­te­ra­cy,' as cal­led for by Ken Tim­mis and colleagues... Read more →

Little things matter, in both virology and your PhD

by Shuxuan Zheng | Blaise Pascal said that "Little things console us because little things afflict us." In the time of CO­VID-19, Pascal's words have never been more prescient. Viruses – those little things behind the global microbiological threat – demand not only our fear but also our respect. Read more →

Three to Tango

by Elio | How many symbioses that involve three partners can you think of? Surely, not many. But here is one, involving a pathogenic fungus, a bacterium, and a fungal virus. Read more →

Of Terms in Biology: Contagion

by Elio | A much used term nowadays, "con­ta­gi­on" or in ad­jec­tive form, "con­ta­gi­ous," is de­rived from La­tin con­tā­giō (touch­ing, con­tact, con­ta­gi­on) re­la­ted to con­tin­gō (touch clo­se­ly). In its ori­gi­nal mean­ing, the term re­fer­red so­le­ly to a dis­ease trans­mis­sible by di­rect phy­si­cal con­tact. Now­adays, its mean­ing has been broad­ened to in­clude all com­mu­ni­cable or in­fect­ious dis­ea­ses. As the Wi­ki­pe­dia says: "Of­ten the word... Read more →

Where Do Phages of Atypical Bacteria Come From? A Snippet.

by Elio | Some time ago, a piece in this blog dealt with the com­ple­xi­ties of the Gram stain. In brief, it said: "In a simp­ler world, all bac­te­ria with a single mem­brane, the mono­derms, would be Gram-po­si­tive, all those with two (the di­derms), Gram-ne­ga­tive... Hah! Were it that simple! Each of these groups... Read more →

Flagella By the Tail

by Elio | We now know that the site of delivery of the phage DNA is not the flagellar filament but rather a region near its base. When the phage reaches it, it can deliver its DNA into the host, as demonstrated by the presence of empty (DNA-less) phage heads at the base of the flagellum. The whole thing takes less than 5 minutes. Read more →

Will the real phage lambda please stand up?

by Nicholas Redmond | Phage infection of a bacterial cell typically begins when the phage’s tail fibers bind a receptor on the host cell, allowing for the ejection of genetic material. At this point, either the lytic or lysogenic cycle begins. Read more →

Secondary Metabolites

by Andy Bodnar, Michelle Prieto, and Carleen Villarreal | The war between bac­te­ria and pha­ges has been wa­ging for eons lon­ger than hu­mans have ex­ist­ed. Con­sequent­ly, ma­ny bacte­ria have de­ve­loped no­vel and unique ways for de­fen­ding them­selves against these fo­reign in­va­ders. Some change their sur­face pro­teins to pre­vent de­tec­tion, like chang­ing a lock on a door. Others give their own lives, ini­tia­ting... Read more →