Ice Recrystallization Inhibition by Amino Acids: The Curious Case of Alpha- and Beta-Alanine

In this work, we report the discovery that the amino acid alpha-alanine – a natural building block of proteins – can inhibit ice recrystallisation (growth) at low millimolar concentrations. To understand how this process works at the molecular level, we combined experimental and computational approaches to measure and simulate the growth of ice in the presence of alpha-alanine or beta-alanine. Despite having the same atomic composition as alpha-alanine, beta-alanine does not inhibit ice growth, making for a puzzling case study on this topic. We traced the inhibition activity of alpha-alanine to its ability to resist becoming overgrown by the growing ice front, characterised by its unfavourable fit within the ice lattice. These results represent a key contribution to our growing understanding of ice recrystallisation inhibition and may translate into improved cryopreservation practices. Have a look at the paper online or grab a pdf here.