Visiting staff

N. Alan Walker

B.Sc.(Hons) Qld, Ph.D. Tas

Visiting Professor


Research Interests

  • Transport problems in plant and ecosystems biophysics, with emphasis on understanding the mechanisms by which solutes are transported across the membranes of plant cells. I work with giant celled plants, which are specially suited to biophysical studies, and with seedcoats and roots of crop plants and waterplants. I am interested in the discovery and characterisation of new solute transport processes, and in understanding how such transport processes determine the electric potential difference between the plant cell interior and the outside. I am especially interested in using models of transport processes to characterise kinetics.
  • I have also worked on the kinetics of solute transport through intercellular junctions in plant cells, on the epidemiology of mycorrhizal infection in plant roots and on the dynamics of root growth, using modelling in each case to clarify the processes involved.
  • I am currently modelling the processes that transport combined nitrogen through an arctic grazed sward ecosystem, from the cyanophytes that fix atmospheric nitrogen to the geese who graze the grass sward and then migrate south for winter.

Selected Publications

  • Efflux of photosynthate and acid from developing seedcoats of Phaseolus vulgaris L.: A chemiosmotic analysis of pump-driven efflux. N.A. Walker, J.W. Patrick, W-H Zhang and S. Fieuw, Journal of Experimental Botany, 46, 539-549, (1995).
  • Turgor-dependent efflux of assimilates from coats of developing seed of Phaseolus vulgaris L.: Water relations of the cells involved in efflux. W-H Zhang, B.J. Atwell, J.W. Patrick and N.A. Walker, Planta, 199, 25-33, (1996).
  • Modelling the current-voltage characteristics of Chara membranes. I.: The effect of ATP removal and zero turgor. M.J. Beilby and N.A. Walker, Journal of Membrane Biology, 149, 89-101, (1996).
  • High affinity potassium uptake in plants. N.A. Walker, D. Sanders and F.J.M. Maathuis, Science, 273, 977-978, (1996).
  • Anion Channel Activity in the Chara Plasma Membrane: Cooperative Subunit Phenomena and a Model. S.R. McCulloch, D.R. Laver and N.A. Walker, Journal of Experimental Botany, 48, 383-397, (1997).
  • The Actions of Calmodulin Antagonists W-7 and TFP and of Calcium on Gating Kinetics of the Calcium-Activated Large Conductance Potassium Channel of the Chara Protoplasmic Drop: A Substate-sensitive Analysis. D.R. Laver, C.A. Cherry and N.A. Walker, Journal of Membrane Biology, 155, 263-274, (1997).

Contact Details 

Mail Address

School of Physics
The University of New South Wales

Email Address

Phone Number

61 2 9385 5712

Facsimile Number

61 2 9385 6060