Recently Designed Multivalent Spike Binders Cannot Bind Multivalently─How Do They Achieve Enhanced Avidity to SARS-CoV-2?

The trimeric spike protein of SARS-CoV-2 has been targeted by antibody mimics that bind near or at the receptor-binding domain to neutralize the virus. Several independent studies have reported enhanced binding avidity for dimers and trimers, where binding domains are connected by short peptides. The enhanced avidity of the multivalent constructs was attributed to their simultaneously binding two or three sites within a single spike trimer.

FtsZ at mid-cell is essential in until the late stage of constriction.

There has been recent debate as to the source of constriction force during cell division. FtsZ can generate a constriction force on tubular membranes , suggesting it may generate the constriction force . However, another study showed that mutants of FtsZ did not affect the rate of constriction, whereas mutants of the PG assembly did, suggesting that PG assembly may push the constriction from the outside.