BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Viruses initially stick to cell membranes through interactions unrelated to fusion proteins. The virus surfs along the fluid surface of the cell and eventually the viral fusion proteins bind to receptor molecules on the cell membrane (4). If only binding occurred, the two membranes would remain distinct.

Detailed explanation-2: -All viruses need to bind to specific receptor molecules on the surface of target cells to initiate infection. Virus–receptor binding is highly specific, and this specificity determines both the species and the cell type that can be infected by a given virus.

Detailed explanation-3: -Attachment proteins of enveloped viruses are generally spike-like and extend from the surface of the virion allowing the attachment protein to serve as the first point of contact with the receptor on the plasma membrane [1].

Detailed explanation-4: -Thus, the enzymatic activity of viral proteases is essential for the production of new, infectious virions by coordinating the processes of viral assembly and maturation, as well as in promoting preferential expression of the viral genome by hijacking host cell control and translation pathways (103).