Stress proteins and cross-protection by heat shock and salt stress in Bacillus subtilis.
Bacillus subtilis induced a set of general stress proteins in response to a salt or heat stress. Cells subjected to a mild heat stress showed a protective response which enabled them to survive otherwise lethal temperatures (e.g. 52 degrees C). In a similar way bacteria were enabled to survive toxic concentrations of NaCl by pretreatment with lower salt concentrations. A mild heat shock induced a cross-protection against lethal salt stress. The pretreatment of cells with low salt, however, was less effective in the induction of thermotolerance than a preceding mild heat stress. Three stress proteins were identified on the basis of their N-terminal amino acid sequences as homologues of GroEL, DnaK and ClpP of Escherichia coli. The role of general and specific stress proteins in the induction of thermotolerance/salt tolerance and cross-protection is discussed.
Völker
U
U
Institute of Microbiology, Ernst-Moritz-Arndt-University, Greifswald, Germany.
Mach
H
H
Schmid
R
R
Hecker
M
M
D049069:ATP-Dependent Proteases; D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000187:drug effects / Q000502:physiology*; D001426:Bacterial Proteins / Q000032:analysis / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D018834:Chaperonin 60; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000032:analysis / Q000502:physiology*; D006358:Hot Temperature; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000032:analysis; D012965:Sodium Chloride / Q000494:pharmacology
D001426:Bacterial Proteins; D018834:Chaperonin 60; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D012965:Sodium Chloride; D049069:ATP-Dependent Proteases; D012697:Serine Endopeptidases; C063842:dnaK protein, E coli