Alternative to fluorescence assays to monitor fusion between Acholeplasma laidlawii cells and liposomes.
OBJECTIVE
To develop a new technique as an alternative to the fluorescence assays and electron microscopy for the purpose of monitoring the cell-liposome fusion.


RESULTS
Acholeplasma laidlawii whole cells did not oxidize Glucose-6-phosphate (G6P) or Fructose-1,6 diphosphate (F1,6DP) as free (unentrapped) substrates, at concentrations 47 and >270 mM, respectively. Lysed A. laidlawii cells oxidized G6P and F1,6DP at lower concentration of 0.8 and 15 mM, respectively. When these substrates were entrapped inside liposomes, at a final concentration of 1.5 mM, and interacted with A. laidlawii whole cells, in an oxygen electrode chamber, an increase in oxygen uptake was evident. This interaction does not have any effect on cell viability.


CONCLUSIONS
The experimental system described here is advantageous over classical fluorescence assays in determining the fate of liposome-entrapped material and raises the possibility of studying the kinetics of metabolic substrates, which are normally excluded from the cell by the cell membrane.
Abu-Amero
K K
KK
Division of Life Sciences, King's College London, 150 Stamford Street, London SE1 9NN, UK. kamero@kfshrc.edu.sa
Halablab
M A
MA
Miles
R J
RJ
D000128:Acholeplasma laidlawii / Q000254:growth & development / Q000502:physiology*; D002462:Cell Membrane / Q000378:metabolism / Q000502:physiology; D005453:Fluorescence; D005635:Fructosediphosphates / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D019298:Glucose-6-Phosphate / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism*; D008561:Membrane Fusion / Q000502:physiology*; D010101:Oxygen Consumption
D005635:Fructosediphosphates; D008081:Liposomes; D019298:Glucose-6-Phosphate; D005947:Glucose; C029063:fructose-1,6-diphosphate