Pseudomonas aeruginosa is a Gram-negative, rod-shaped bacterium, resistant to many antibiotics. It can cause several chronic infections such... Show morePseudomonas aeruginosa is a Gram-negative, rod-shaped bacterium, resistant to many antibiotics. It can cause several chronic infections such as lung, bloodstream, urinary tract, and surgical wound infections. This bacterium produces biofilms which confer resistance to hazardous environments. P. aeruginosa contains five stages of colony development, which are planktonic attachment, cell to cell adhesion, proliferation, maturation, and dispersion. After five stages, biofilms of P. aeruginosa are matured. The biofilm structure produced by P. aeruginosa is important for cell survival, providing protection and resistance to harsh environment and antibiotics. In this research, the biofilms formed by wildtype strain PA01 and mutated strains of PA14, including NDH-2, NQR F, and NUO I, were developed in LB medium and Artificial Urine Medium separately for 96 hours. After washing, collecting, and staining the biofilms, the analyses of measurement of OD562 showed that in LB medium, PA01 formed more biofilms than mutants while NUO I and NDH2 had less biofilms, although not significantly. In AUM the situation was different. PA01 formed least biofilms while NQR F formed largest biofilms than any other strains. Also, the NDH-2 formed more biofilms than NUO I in AUM. The deficiencies of enzymes loss in those strains result in growing biofilm concentrations. Because the difference was not significant, we can only say that the NQR and NADH dehydrogenases have important roles in biofilm formation. Show less