We develop Proprietary Antiviral Drugs
Viruses carry minimal genetic information as they rely, for the most part, on host cellular machinery to multiply. Coronavirus has a positive sense RNA genome consisting of approximately 30,000 nucleotides, a size that places Coronavirus among the larger sized viruses. A positive-sense RNA genome is effectively a messenger RNA which allows the virus to express its genes immediately upon gaining entry into the host cell without the need for any prior replication or transcription steps, as is the case with negative-sense RNA or DNA viruses. This is part of what makes Coronavirus a highly aggressive pathogen. Many of the causative agents of serious human diseases are positive-sense RNA viruses, including Hepatitis C, Zeka, Polio, West Nile, Dengue, Cardiovirus, and many others. Some positive-sense RNA viruses, such as the rhinoviruses that cause the common cold, are less clinically serious, but they are responsible for widespread morbidity on a yearly basis.
The initial genome expression products of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, are two large polyproteins, referred to as pp1a and pp1ab. These two polyproteins are cleaved at 13 specific sites by the main Coronavirus virus encoded protease (Mpro or 3CLpro) to generate a number of mature viral proteins essential for viral replication. Mpro represents an attractive anti-viral drug development target as it plays a central role in the early stages of viral replication. The crystal structure of Mpro shows the presence of an active site Cysteine (Cys145) and a coordinated active site Histidine (His41), both of which are essential for the enzyme’s proteolytic activity.