Post-translational processing of viral fusion proteins confers this property, which allows acidity to trigger a conformational change. For 10 points each:
[10m] Name this property of proteins whose conformations correspond to a local energetic minimum but require further energetic input to achieve the conformation corresponding to a global energetic minimum.
ANSWER: metastability [or word forms like metastable; reject “unstable” or “stable”]
[10h] Two answers required. HIV’s metastable Env protein consists of three dimers of these two glycoproteins. Upon contact with CD4 and CCR5, one of these proteins is shed while the other changes conformation to open a fusion pore. Name both.
ANSWER: gp120 AND gp41 [accept envelope glycoprotein gp120 in place of “gp120”; accept envelope glycoprotein gp41 in place of “gp41”; accept answers in either order]
[10e] The best-characterized metastable viral protein is hemagglutinin, whose isotypes, along with those of neuraminidase (“nyur-am-IN-ih-daze”), provide the “H” and “N” numbering for naming strains of this virus.
ANSWER: influenza virus [accept influenza A virus; prompt on flu virus]
<Biology>