SARS-CoV-2 is a beta-coronavirus. The spike glycoprotein of SARS-CoV-2 can attach to host cell membrane by recognizing and binding to the angiotensin-converting enzyme 2 (ACE2) receptor, and transmembrane protease type 2 (TMPRSS2) also plays a critical role in the viral invasion [1]. Based on the homology modeling of receptor binding domain subdomain-1, the structure of SARS-CoV-2 shows about 73.96% sequence identity with SARS-CoV, which might explain the resemblance in biochemical mechanism [2].