FIG 4.

Osmotic stress adaptation of wild-type UA159 and SMΔtrk2 in limited K⁺. Strains were grown in MMGK with 5 mM, 25 mM, and 50 mM KCl for 24 h. To examine growth rate under osmotic stress, cells were supplemented with 0.4 M NaCl (right) and compared to those without NaCl (left). Final growth yields in various K⁺ concentrations with or without 0.4 M NaCl for four biological and three technical replicates are presented. Student's t test was used to determine statistical significance (*, P < 0.05) compared to wild-type strain UA159.