Cryobiology and Anhydrobiology

Physical stresses in cryobiology and anhydrobiology. Much of the cellular damage produced by environmental freezing is due to freezing-induced, osmotic dehydration and to the rehydration during thawing. Both dehydration and rehydration impose mechanical stresses on membranes and macromolecules and several of the resultant strains have been correlated with cellular freezing and thawing damage. In collaboration with Gary Bryant of RMIT, we use NMR and thermodynamic techniques to measure stresses and strains in model membrane systems and in some suspended cells. For more details, see Biophysics of cryobiology and anhydrobiology

Freezing damage in leaves. Freezing damage limits the range of many plant species, and the re-establishment of eucalypt forests. In collaboration with Marilyn Ball of ANU, we study the way ice forms in the leaves of eucalypts, using infra-red imaging and numerical modelling of radiation, convection, conduction and nucleation.

Selected Publications

Wolfe, J. (2002) "Cellular Thermodynamics" Encyclopedia of Life Sciences. http://www.els.net London: Nature Publishing Group. April 2002.
Wolfe, J., Bryant, G. and Koster, K. (2002) ""What is unfreezable water, how unfreezable is it and how much is there?" Cryo-Letters, 23, 157-166.
Wolfe, J. and Bryant, G. (2001) "Cellular cryobiology: thermodynamic and mechanical effects" International Journal of Refrigeration. 24, 438-450.
Bryant, G., K.L. Koster and J. Wolfe. (2001) "Membrane behavior in seeds and other systems at low water content: the various effects of solutes" Seed Science Research, 11, 17-25.
Wolfe, J. and Bryant, G. (1999) "Freezing, drying and/or vitrification of membrane-solute-water systems" Cryobiology, 39, 103-129.

http://extra.idealibrary.com/production/cryo/1999/39/2/cryo.1999.2195/2195a. pdf

Yoon, Y. H., Pope, J. and Wolfe, J. (1998) "The effects of solutes on the freezing properties of and hydration forces in lipid lamellar phases." Biophys. J., 74, 1949-1965.

Lutze, J.L., Roden, J.S., Holly, J.C., Wolfe, J., Egerton, J.J.G. and Ball, M.C. (1998) "Elevated atmospheric [CO2] promotes frost damage in evergreen tree seedlings" Plant, Cell and Environment, 21, 631-635.

Yoon, Y. H., Pope, J. and Wolfe, J. (1997) "Freezing-induced hydration forces between phosphatidylcholine bilayers - the effect of osmotic pressure." Colloids and Surfaces A, 129, 425-434.

Bryant, G. and Wolfe, J. (1992) "Interfacial forces in cryobiology and anhydrobiology" Cryoletters 13, 23-36.