Biochemical and biophysical studies of Bacillus subtilis envelopes under hyperosmotic stress.
The behaviour and state of the envelopes from B. subtilis cultures grown in Luria Bertani (LB) medium with and without 1.5 M NaCl are compared. Under hypertonic conditions, the hydrophobicity of the cultures increases. The phospholipid and fatty acid (FA) compositions show important differences: a higher cardiolipin (CL) content [at the expense of phosphatidylglycerol (PG)], and a higher unsaturated and straight chain FA content. The fluidity of the membranes, determined with fluorescent probes, indicates an increase in viscosity of the cytoplasmic membrane. The consequences of these variations in membrane permeability and osmotolerance are discussed.
López
C S
CS
Instituto de Biología Celular, Facultad de Medicina, Buenos Aires, Argentina.
Heras
H
H
Garda
H
H
Ruzal
S
S
Sánchez-Rivas
C
C
Rivas
E
E
D001412:Bacillus subtilis / Q000737:chemistry / Q000378:metabolism*; D002463:Cell Membrane Permeability; D005227:Fatty Acids / Q000032:analysis; D008560:Membrane Fluidity; D008563:Membrane Lipids / Q000032:analysis*; D010743:Phospholipids / Q000032:analysis; D014882:Water-Electrolyte Balance
D005227:Fatty Acids; D008563:Membrane Lipids; D010743:Phospholipids