Characterization of Komagataeibacter xylinus by a polarization modulation imaging method

Komagataeibacter xylinus (K. xylinus) has been used for a long time as one of the main cellulose producers among bacterium. In order to gain a better understanding of the physiological and biochemical mechanisms of cellulose production, an efficient and non-invasive visualization method is highly demanded to monitor the morphological changes of K. xylinus during each stage of its development. In this study, a polarization parametric indirect microscopic imaging (PIMI) technique was applied to image the morphology variations of K. xylinus. The optical field with precisely controlled polarization status was incident on the sample and far-field images of the sample were taken under different illumination polarization. In the calculated parametric images, sub-diffraction features related to the morphology details of the K. xylinus were visualized with high contrast and spatial resolution, which is typically irresolvable in conventional microscopic images. Finite-difference time-domain simulations verified the visualized scattering distributions in PIMI imaging results. We believe these pieces of evidence proved the possibility of developing a platform for characterizing the structures and morphological changes of cells in the cultivating process. (paper)