Premium
Crystallization of a trimeric human T cell leukemia virus type 1 gp21 ectodomain fragment as a chimera with maltose‐binding protein
Author(s) -
Center Rob J.,
Kobe Bostjan,
Wilson Kirilee A.,
Teh Trazel,
Kemp Bruce E.,
Poumbourios Pantelis,
Howlett Geoffrey J.
Publication year - 1998
Publication title -
protein science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.353
H-Index - 175
eISSN - 1469-896X
pISSN - 0961-8368
DOI - 10.1002/pro.5560070715
Subject(s) - ectodomain , chimera (genetics) , virology , maltose binding protein , biology , chemistry , microbiology and biotechnology , recombinant dna , genetics , fusion protein , receptor , gene
We present a novel protein crystallization strategy, applied to the crystallization of human T cell leukemia virus type I (HTLV‐1) transmembrane protein gp21 lacking the fusion peptide and the transmembrane domain, as a chimera with the Escherichia coli maltose binding protein (MBP). Crystals could not be obtained with a MBP/gp21 fusion protein in which fusion partners were separated by a flexible linker, but were obtained after connecting the MBP C‐terminal α‐helix to the predicted N‐terminal α‐helical sequence of gp21 via three alanine residues. The gp21 sequences conferred a trimeric structure to the soluble fusion proteins as assessed by sedimentation equilibrium and X‐ray diffraction, consistent with the trimeric structures of other retroviral transmembrane proteins. The envelope protein precursor, gp62, is likewise trimeric when expressed in mammalian cells. Our results suggest that MBP may have a general application for the crystallization of proteins containing N‐terminal α‐helical sequences.