Fig. 2

Ami1_Di can suppress cell separation defects in E. coli amidase mutant. (A) Phase contrast micrographs representing cells of strain RP21 (MG1655 ΔamiA::frt ΔamiC::frt /pBAD18), RP101 (MG1655 ΔamiA::frt ΔamiC::frt /pBAD18ami1_Di) induced with 0.4% L-arabinose (ara). Cells were grown in LB medium at 37 °C to an OD₆₀₀ ∼ 0.2 and induced with 0.4% L-arabinose (ara). RP101 strain grown with 0.2% glucose (glu) was used as a negative control. After 6 h of induction, cells were collected and 6 µL was immobilized on 1XPBS agarose pad and imaged. In the presence of 0.4% L-arabinose complementation of chain-forming double-amidase mutant by ami1_Di resulted in a reduction in the chaining phenotype. (B) Quantitative analysis of phase contrast micrographs of strains RP21 and RP101. Cells were counted as mentioned in Materials and Methods. RP101 shows a reduction in chains and an increment in singlets and doublets. Datasets are from three independent experiments, and error bars represent standard deviation. P value = RP21 vs. RP101 + 0.2% glu (glucose), p < 0.05**, RP21 vs. RP101 + 0.4% ara (L-arabinose), p < 0.05**. No. of cells – Total number of cells counted for each strain