Effects of AFGP on Freezing

The freezing temperature curve in the presence of 50 mM NaCl parallels that for solutions of AFGP alone, indicating that the activity of the glycoprotein is strictly additive to the freezing-temperature depression owing to the sodium chloride. This result clearly indicates 

Freezing and Melting of Water and Solution of Antifreeze Glycoproteins (AFGP) in Water  

1 Water and AFGP solution was initially frozen at -3°C and then allowed to melt at +0.1°C until 5-10% of solution remained as ice crystals. The temperature was then adjusted to 0.0°C and periodically lowered and then raised as indicated. The times at each temperature intermediate between freezing and melting were 5-10 minutes. All observations were made microscopically. 

Effects of Freezing Solutions of AFGP on the Characteristics of the Ice and AFGP 

In comparison to most studies on the mechanisms of action of a protein, similar studies on AFGP must necessarily be done under conditions that present special problems, namely, the phase change of water to ice. These require the design of experiments to make observations on the ice, the surface of the ice, the surface of growing ice crystals, and solutions in the presence of ice crystals. 

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