The cells of Pseudomonas syringae, a plant pathogen, can cause ice nucleation via specific surface proteins.

References

"P. syringae is one of the few plant pathogens known to be disseminated up into clouds (Jayaweera and Flanagan, 1982; Sands et al., 1982). It is also scrubbed from the air during rain (Constantinidou et al., 1990). Many strains of this bacterium are ice nucleation-active (Lindow, 1983), are known to survive freezing as well as induce freezing, and it has been suggested that they might even have a role in inciting rainfall via their ice nucleation activity (Morris et al., 2004)." (Morris et al. 2007:85)

"Antifreeze proteins (AFPs) inhibit the growth of ice, whereas ice-nucleation proteins (INPs) promote its formation…Although several organisms have been identified as having ice-nucleation activity, the best characterized by biochemical methods are the bacterial INPs. Of these INPs, that of Pseudomonas syringae is often used as a representative protein." (Graether and Jia 2001:1169)

Journal article
Surprising niche for the plant pathogen Pseudomonas syringaeMorris, C. E.; Kinkel, L. L.; Xiao, K.; Prior, P.; Sands, D. C.

Journal article
Modeling Pseudomonas syringae ice-nucleation protein as a b-Helical proteinGraether, SP; Jia, Z

Living System/s

Organism
BacteriaBacteriaKingdom

Organism
PseudomonasGenus