A sucrose-binding protein homologue from soybean exhibits GTP-binding activity that functions independently of sucrose transport activity.

The sucrose binding protein (SBP) has been implicated as an important component of the sucrose uptake system in plants. SBP-mediated sucrose transport displays unique kinetic features and the protein is not similar to other transport proteins. Here, we report the characterization of a member of the SBP family from soybean [Glycine max (L) Merrill] designated S64 or SBP2.