Dr. Kevin Ahern is a biochemistry professor and Great Courses instructor. He teaches at Oregon State University and led our lecture series on biochemistry and molecular biology. His new video offers insights on the coronavirus.
The White House, health groups, and the news media seem to break new information about the novel coronavirus all the time. Similarly, every day, the virus is studied and the populace that’s exposed to it either recovers or succumbs to the COVID-19 disease. In turn, existing information on it is either amended or proven outdated.
Why Antibiotics Don’t Work on the Coronavirus
Many people think of viruses as malevolent cellular organisms invading our bodies. One of the most surprising things about viruses is that, technically, they aren’t even cells.
“This is why we cannot use antibiotics against viruses,” said Dr. Kevin Ahern, Professor of Biochemistry and Biophysics at Oregon State University. “Antibiotics are drugs that kill bacteria by blocking processes bacterial cells require to live—but viruses are not cells at all. Instead, viruses are very tiny particles, much smaller than even a bacterial cell.”
Dr. Ahern said that not only are viruses not cellular, but they aren’t even, technically, living things. Instead, they’re actually tiny particles that are much smaller than bacteria. They carry the information required to make copies of themselves, but they either store that information in a double-helix of DNA or—in the case of the coronavirus—a single strand of ribonucleic acid (RNA), which is a related molecule.
How the Coronavirus Replicates Itself
“Viruses, in general, have none of the actual materials and few of the tools they need to make more copies of themselves,” Dr. Ahern said. “To reproduce, a virus must sneak into a cell and steal its resources and raw materials.”
It’s also been established that the term “corona” in “coronavirus” comes from the latin word for “crown,” because the ball-shaped virus structure has crown-like spikes sticking out of it that resemble a crown. Dr. Ahern said these spikes are important for understanding how the virus attacks our cells.
“So, a coronavirus breaks in by using its spike protein as a sort of key, which it inserts into another protein, called a receptor, on the surface of the cell it infects,” he said. “This allows the virus to gain entry into the cell in a process called endocytosis, where the virus is absorbed into the inner portion of the cell. Once inside, the coronavirus then releases instructions for making new copies of itself, hijacking cellular resources to make thousands of new virus particles that can then go on to infect more cells.”
The Surprising Reason Why Soap Works
Dr. Ahern said that the coronavirus’s RNA is wrapped up in a structure of proteins that gets coated in a greasy layer of fatty molecules known as lipids. This is where washing your hands with soap and water comes in.
“The greasy lipid coating of the virus is dissolved by soap—without that protective layer, the virus falls,” he said. “Soap also disrupts the structure of the spike proteins and the proteins coating the RNA in the core of the virus. Disrupted proteins no longer function, so the spike protein can’t bind to the cellular receptors.”
Dr. Ahern said that these two actions expose the coronavirus’s RNA directly to the environment, which is bad news for the virus because RNA is “extraordinarily unstable” outside the virus and thus “readily destroyed.” Alcohol-based hand sanitizers also disrupt the virus’s proteins.
Dr. Kevin Ahern contributed to this article. Dr. Ahern is a Professor of Biochemistry and Biophysics at Oregon State University (OSU), where he also received his Ph.D. in Biochemistry and Biophysics. He has served on the OSU faculty in Biochemistry/Biophysics since the mid-1990s.