Fig 7.
Accumulation of (p)ppGpp in S. mutans strains in the presence or absence of hydrogen peroxide. (p)ppGpp accumulation of the wild-type strain compared (A) with that of the ΔrelP, ΔrelQ, and ΔrelPQ mutants and (B) with that of the Δpta, ΔrluEΩ, and ΔrluE ΔptaE mutants. Cells growing exponentially in FMC medium were labeled with [32P]orthophosphate and subjected to the stress conditions for 1 h. Extracts derived from treatment of the cells with 13 M formic acid were normalized to counts per minute (CPM) and spotted onto PEI-cellulose plates for TLC using 1.5 M KH2PO4 buffer.