Academic Staff
Mary J. Beilby

B.Sc., Ph.D. UNSW, MAIP, Grad. Cert. H. Ed.

Senior Lecturer

Department and Research Groups


Mary J. Beilby

Research Interest

I study electrical properties of membranes surrounding living plant cells. Many life processes involve moving ions in and out of the cell. Potential difference (p.d.) across the membrane can be measured and controlled. The ionic currents flowing through a multitude of specific transport systems (constituted by protein molecules imbedded in the lipid bilayer) show characteristic p.d. dependencies. Such current-voltage (I/V) curves allow isolation, characterisation and modelling of different transporters. Work has been done on the electrogenic proton pump, K+ channels, H+/OH- channels, Cl- channels, the action potential, amine uniport and Cl-/2H+ symport. My new project investigates the role of some of these transporters play in the cell response to varying salinity of the outside medium. The experiments are performed on giant-celled algae Characeae (single cells are up to 1 mm in diameter and several cm in length), which allow extensive manipulation, such as perfusion of the cell contents with artificial solutions, removal of vacuole or permeabilization of the outer cell membrane. The patch clamp technique is also employed to measure single channel currents in the inner cell membrane, the tonoplast.

Selected Publications

  • Voltage dependence of the Chara proton pump revealed by current-voltage measurement during rapid metabolic blockade with cyanide. M.R. Blatt, M.J. Beilby & M. Tester, J. Membrane Biol., 114, 205-223 (1990).
  • The Chara plasmalemma at high pH: voltage dependence of the conductance at rest and during excitation, M.J. Beilby & M.A. Bisson, J. Membrane Biol., 125, 25-39 (1992).
  • Modelling the current-voltage characteristics of Chara membranes: I. The effect of ATP removal and zero turgor. M.J. Beilby & N.A. Walker. Accepted by J. Membrane Biol. (1996).
  • Turgor regulation in Lamprothamnium papulosum. I. I/V analysis and pharmacological dissection of the hypotonic effect. M.J. Beilby & V.A. Shepherd. Accepted by Plant Cell Environ. (1996).

Contact Details 

Mail Address

School of Physics
The University of New South Wales

Email Address

Phone Number

61 2 9385 5463

Facsimile Number

61 2 9385 6060