Natural and Recombinant SARS-CoV-2 Isolates Rapidly Evolve In Vitro to Higher Infectivity through More Efficient Binding to Heparan Sulfate and Reduced S1/S2 Cleavage
a Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA ; b UAB Genomics Core Facility, Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA