Part:BBa_K3782000

FfIBP is a protein coding region that codes for an ice binding protein (IBP). IBPs, or more specifically antifreeze proteins (AFP), can bind to ice crystals and thereby prevent further ice growth. They are produced by organisms to survive in extremely cold environments. Activities of AFPs can be characterized by their thermal hysteresis (TH) or by their ice recrystallization inhibition (IRI). TH activity corresponds to the lowering of the freezing point without changing the melting point of a solution. IRI activity inhibits the growth of large ice crystals at the expense of smaller ones. The combination of these activities, which vary depending on the protein structure, prevents the freezing of body fluids and cell damage in organisms that live in environments with extremely cold temperatures.

FfIBP is naturally produced by the Gram-negative Antarctic bacterium Flavobacterium frigoris PS1. Its TH activity is around 2.5 K at 50 µM.