Abstract
Bacillus subtilis YS11, when the temperature shifted from 37 to 48°C, synthesized stress proteins more (78 kDa and 86 kDa). When treated with 1.0 M NaCl, no stress proteins were induced. The strain, when subjected to heat shock and salt stress, synthesized another stress protein more quickly (50 kDa).
First, using the strain subjected to heat shock and salt stress, the effect of salt on the growth of bacterial cells was investigated. At 37°C, salt completely inhibited the cellular growth at 2.0 M, compared to 1.2 M using the strain not subjected to stress. At 44°C, salt completely inhibited the cellular growth at 2.0 M, compared to 1.2 M using the strain not stressed. Second, the effect of salt on growth of phages M2 and SPO1 was investigated in relation to phage control with salt at high temperatures. At 37°C, salt completely inhibited the growth of phages at 1.6-1.8 M, compared to 1.2-1.3 M using the strain not stressed. At 44°C, salt completely inhibited the phage growth at 1.6-1.8 M, compared to 1.2-1.5 M using the strain not stressed.
