How do snowflakes form
People often wonder how a snowflakes forms such a unique and beautiful structure? The answer actually lies within a microorganism. As you may be aware of microbes, commonly known as germs, are everywhere. They are in the food we eat, the air we breathe, and on the surface of every plant.
Scientists first became aware of the unique abilities of Pseudomonas syringae when witnessing the freezing of water at higher temperatures than usual. The laws of thermodynamics are quite consistent for chemicals undergoing phase change and water freezes consistently at ranges of -2°C – 0°C depending also on the atmospheric pressure. However scientists were noticing ice crystals forming on the leaves of plants at temperatures around 2°C, which should not be possible thermodynamically. Upon further research of the bacterium in question, Pseudomonas syringae were found to be producing very unique protein. This protein is an ice nucleation protein, INP, which is capable of increasing the freezing temperature of water. The mechanism that allows the INP protein to do this thought to be literally gripping water molecules and holding them together to crystallize easier. Unfortunately the bacterium can cause enormous amounts of frost damage to crops so it needed to be controlled.
Pseudomonas syringae forms snowflake
One group of researchers have actually genetically modified the Pseudomonas to no longer generate and INP.These genetically modified bugs can be sprayed on plants and will out competing the wild type bacteria. The ice nucleation proteins have also been linked to the foundation most snowflakes from strains of Pseudomonas syringae living in the atmosphere. Think about that next time you hold your tongue out to catch some snowflakes. Snowboarders and skiers rejoice with our development of man-made snow, yet a common way has been to actually isolate ice nucleation proteins.
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