The influenza A virus became amantadine-resistant around the world in 2005. The video to the right provides one explanation for the mechanism of the change. The protein on the right is the new resistant structure and the one on the left is the amantadine-sensitive structure. In the simulation, amantadine is dragged through the channel. If not for the unnatural dragging force, the drug would normally get stuck about half-way through. In the video clip above, the amantadine blocks water from coming into the channel at that half-way point by turning down, whereas on the right it stays up-facing, dragging water, and protons, with it. These results have been published (see Figure 4 in the linked article).
The Busath Lab focuses on two research projects, described in the next tab: Influenza Antiviral Development and Chronic Pain Mechanism and Alleviation. As a career biophysicist, Dr. Busath has, in past years, explored the origins of selectivity in rudimentary ion channels such as gramicidin, examined the protein channel function of botulinum toxin heavy chain, evaluated the role of general anesthetic and NSAID interaction with lipid monolayers and bilayers, and assessed proton transport through influenza A M2 channels. The two current research projects are natural outgrowths with broad missions. In the Influenza Anti-viral project, we hope to help protect the world against a pandemic arising from bird flu by developing inescapable blockers to the influenza proton channel. In the Chronic Pain project we hope to ascertain, with the help of brain imaging, the mechanism by which transcutaneous electrical stimulation can alleviate neuropathic pain to help lay the scientific foundation for drug-free relief of unnecessary chronic pain.