SUMMARY : A strain of Bacillus cereus known to produce penicillinase adaptively was tested for penicillin sensitivity at different temperatures. With small inocula, the organisms grew freely at 37° in concentrations of penicillin up to a hundred times greater than those which completely suppressed their growth at 42°. This difference in apparent sensitivity almost disappeared when the inoculum was very heavy or consisted of cells which had been allowed to adapt by previous growth in the presence of penicillin.
PasteurL.,
JoubertJ.,
ChamberlandC.1878; La theorie des germes et ses applications à la médecine et a la chirurgie. Bull. Acad. Méd., Paris 2nd ser. 7:432
PollockM.R.1945; The influence of temperature on the adaptation of ’tetrathionase ’ in washed suspensions of Bact. paratyphosum B. Brit.
. J. exp. Path. 26:410