FIG 3.

Influence of exogenous MG, or glucose, on the intracellular MG level in various strains of Synechocystis PCC 6803. Portions (100 ml) of mid-log-phase cultures, incubated for 18 h in standard liquid MM without or with 100 μM methylglyoxal (MG) or 50 mM glucose (Glc), were used to measure the intracellular concentration of MG in the WT strain or the mutants lacking Sll0067 (Δsll0067), MG synthase (Δmgs), or depleted in GSH (ΔgshB). The data are expressed as means ± the SD of three experiments. ND, not detected; *, significant difference between mutants and the WT (t test, P < 0.05).