Viruses are obligate intracellular parasites: they must enter a cell to reproduce. To gain access to the cell interior, a virus must first bind to one or more specific receptor molecules on the cell surface. Cell receptors for viruses do not exist only to serve viruses: they also have cellular f... Read More
The hemagglutinin (HA) and neuraminidase (NA) glycoproteins of the influenza virus particle serve distinct functions during infection. The HA binds sialic acid-containing cellular receptors and mediates fusion of the viral and cell membranes, while the NA removes sialic acids from glycoproteins.... Read More
The Amazon river is the largest river in the world. It drains the entire Amazon rainforest, sending leftover nutrients, detritus, and minerals from the South American jungle out into the tropical Atlantic ocean. This runoff forms a freshwater plume, hundreds of miles across, that profoundly affe... Read More
Pick an archaeon, any archaeon, and you will find it has a story to tell. Not all archaea are exotic but plenty of them are. These stalwarts live in environments we humans call extreme, where they carry out what to us seem extreme types of metabolic conversions. Most have come rather late into o... Read More
As a virologist who has worked on poliovirus since 1979, I would be remiss if I did not note that today, 24 October, is World Polio Day. World Polio Day was established by Rotary International over a decade ago to commemorate the birth of Jonas Salk, who led the first team to develop a vaccine a... Read More
A new virus called Pithovirus sibericum has been isolated from 30,000 year old Siberian permafrost. It is the oldest DNA virus of eukaryotes ever isolated, showing that viruses can retain infectivity in nature for very long periods of time. Read More
Methicillin-resistant S. aureus (MRSA) constitutes approximately 50% of clinical S. aureus isolates and is most commonly the result of production of a mutated pencillin-binding protein, PBP2a, which is able to carry out essential cell wall synthesis functions while maintaining a low-affinity for... Read More
Viruses are the most abundant biological entities on the planet with approximately 1030 in the world’s oceans at any time. As such, they play a central role in global nutrient cycling. Despite their ecological importance, little is known about how viruses interact with their hosts due to the dif... Read More
The abilities of bacterial organisms to utilize the various strategies to resist antimicrobial compounds are all genetically encoded.
Intrinsic resistance is that type of resistance which is naturally coded and expressed by all (or almost all) strains of that particular bacterial species. An... Read More
This episode: Bacteria are able to incorporate DNA from the environment into their genomes, even if it's thousands of years old!
(9.6 MB, 10.5 minutes)