Novel dimeric β-helical model of an ice nucleation protein with bridged active sites.

ABSTRACT:

Background

Ice nucleation proteins (INPs) allow water to freeze at high subzero temperatures. Due to their large size (>120 kDa), membrane association, and tendency to aggregate, an experimentally-determined tertiary structure of an INP has yet to be reported. How they function at the molecular level therefore remains unknown.

Results

Here we have predicted a novel β-helical fold for the INP produced by the bacterium Pseudomonas borealis. The protein uses internal serine and glutamine ladders for stabilization and is predicted to dimerize via the burying of a solvent-exposed tyrosine ladder to make an intimate hydrophobic contact along the dimerization interface. The manner in which PbINP dimerizes also allows for its multimerization, which could explain the aggregation-depe

SUBMITTER: Garnham CP 

PROVIDER: S-EPMC3196904 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature