Fig. 5

AP enzymatic activity under conditions of P_i limitation in His-producing and non-producing E. coli strains with different pitA alleles. MG1655, wild-type MG1655; MG1655 ∆pitA, MG1655 [ΔpitA::Km^R]; KF37, MG1655⁺ [ΔpurR P _his -ΔhisL′hisG^E271KDCBHAFI]; KF37 ∆pitA, KF37 [ΔpitA:: Km^R]. Average data from 3 independent experiments are represented, and error bars show the standard deviation (SD). PhoA enzymatic activity was analyzed 24 h after P_i exhaustion