Analysis of the effect of acid stress in Lactococcus lactis MG1363. Lactococcus cremoris subsp. cremoris MG1363

To understand the system response to pH changes in the environment, the expression of genes during the pH shift was investigated. Pre-adaptation effects were examined by comparing the effects seen with cells pre-grown in pH 5.1 or pH 6.5 to those occuring after a sudden pH change (pre-grown in pH 6.5, and suspended in buffer of pH 5.1). Overall design: mRNA of L. lactis MG1363 cells grown at pH 6.5 and suspended in 50 mM KPi buffer, pH 5.1 and of those grown at pH 5.1 and suspended in 50 mM KPi buffer, pH 5.1 were compared. Control experiment was performed with mRNA of cells grown at pH 6.5 and suspended in buffer of pH 6.5 compared to that of cells grown in pH 5.1 and suspended in buffer of 5.1.