Crystal structure of human T cell leukemia virus type 1 gp21 ectodomain crystallized as a maltose-binding protein chimera reveals structural evolution of retroviral transmembrane proteins.

ABSTRACT: Retroviral entry into cells depends on envelope glycoproteins, whereby receptor binding to the surface-exposed subunit triggers membrane fusion by the transmembrane protein (TM) subunit. We determined the crystal structure at 2.5-A resolution of the ectodomain of gp21, the TM from human T cell leukemia virus type 1. The gp21 fragment was crystallized as a maltose-binding protein chimera, and the maltose-binding protein domain was used to solve the initial phases by the method of molecular replacement. The structure of gp21 comprises an N-terminal trimeric coiled coil, an adjacent disulfide-bonded loop that stabilizes a chain reversal, and a C-terminal sequence structurally distinct from HIV type 1/simian immunodeficiency virus gp41 that packs against the coil in an extended antiparallel fa

SUBMITTER: Kobe B 

PROVIDER: S-EPMC16330 | biostudies-literature | 1999 Apr

REPOSITORIES: biostudies-literature