A lot of human activities have negative impact on water quality and sometimes result in the biological water contamination. Currently used chemical (chlorine, ozone, and etc.) and physical (UV) water disinfection methods have strong environmental disadvantages or suffers from limited efficiency. To overcome these problems, scientists suggest to use photocatalyst activated advanced oxidation processes. One of the most studied photocatalysts which attracts a lot of research interest is titanium dioxide. TiO2 application for the disinfection of water, air or surfaces is increasingly encouraged by researchers. However, to unlock its full potential it is highly desirable to make it suitable for the visible light activation. In the current study the effect of visible light assisted photocatalytic treatment to the outer membrane permeability of