Disulfide bond stabilization of the hexameric capsomer of human immunodeficiency virus.

ABSTRACT: The human immunodeficiency virus type 1 capsid is modeled as a fullerene cone that is composed of approximately 250 hexamers and 12 pentamers of the viral CA protein. Structures of CA hexamers have been difficult to obtain because the hexamer-stabilizing interactions are inherently weak, and CA tends to spontaneously assemble into capsid-like particles. Here, we describe a two-step biochemical strategy to obtain soluble CA hexamers for crystallization. First, the hexamer was stabilized by engineering disulfide cross-links (either A14C/E45C or A42C/T54C) between the N-terminal domains of adjacent subunits. Second, the cross-linked hexamers were prevented from polymerizing further into hyperstable capsid-like structures by mutations (W184A and M185A) that interfered with dimeric association

SUBMITTER: Pornillos O 

PROVIDER: S-EPMC3050670 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature