Figure 1From: Polyamine stress at high pH in Escherichia coli K-12Extreme-acid survival in the presence of polyamines. The mean survival at pH 2 after 2 h in the presence of each polyamine (10 mM) was divided by the mean survival of a sample diluted from the same overnight culture without exogenous polyamines. The mean of six independent cultures is shown, +/- SEM.Back to article page