Figure 6. P. aeruginosa strains mutated in key c-di-GMP genes show an attenuated response to IONP-induced hyperthermia.

Biofilms of P. aeruginosa wild type, lapG (c-di-GMP responsive periplasmic protease) and bifA (c-di-GMP phosphodiesterase) mutant strains were grown in test tubes for 24 h, before being treated with POEGA-b-PMAEP@IONPs (1 mg mL⁻¹) and exposed to an alternating magnetic field for 20 min, and finally analysed by crystal violet (CV) staining as described before. MI, magnetic induction. Error bars represent standard errors (n = 3). Asterisks indicate statistically significant difference of treatment versus untreated culture (**P < 0.01; ****P < 0.0001; ns, not significant).