Conformational changes of rBTI from buckwheat upon binding to trypsin: implications for the role of the P(8)' residue in the potato inhibitor I family.

ABSTRACT: BWI-1 (buckwheat trypsin inhibitor), a member of the potato inhibitor I family, suppresses the growth of T-acute lymphoblastic leukemia cells and induces apoptosis in human solid tumor cell lines. Here, we report the crystal structure of rBTI (recombinant buckwheat trypsin inhibitor), a recombinant protein of BWI-1, at 1.84 Å resolution and the structure of rBTI in complex with bovine trypsin at 2.26 Å resolution. A conformational change of Trp53 at the P(8)' position in rBTI was observed upon its binding to trypsin, which is not seen in other members of the potato inhibitor I family reported previously. The role of the P(8)' residue in the potato inhibitor I family was examined by measuring the association and dissociation rates of four rBTI mutants with different substitutions at the P(2

SUBMITTER: Wang L 

PROVIDER: S-EPMC3115953 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature