Spike Glycoprotein of SARS-CoV-2 (Omicron XBB.1.5) (S protein)

The spike glycoprotein (S protein) is a large, trimeric, class I fusion protein found on the surface of SARS-CoV-2, including its Omicron XBB.1.5 variant. It mediates viral entry into host cells by binding to the angiotensin-converting enzyme 2 (ACE2) receptor and facilitating membrane fusion. The S protein is also the primary target for neutralizing antibodies and vaccines. Omicron XBB.1.5 variant has specific mutations that enhance immune evasion.

Other names

SARS-CoV-2 Spike proteinOmicron XBB.1.5 Spike protein

The spike glycoprotein mediates viral attachment to host cells via ACE2 binding followed by triggering virus-cell membrane fusion through irreversible structural rearrangements post-cleavage and activation. Neutralizing antibodies block ACE2 binding and/or prevent conformational changes necessary for membrane fusion.