Figure 1.

The hypermucoid phenotype of K. pneumoniae is associated with inhibition of cell adherence and internalization. Mucoviscosity (a) and uronic acid production (b) in hypervirulent Klebsiella strains HvKP1, HvKP2, HvKP3, HvKP4, and classical Klebsiella strains cKP1, cKP2, cKP3, cKP4. Invasion assay of selected clinical K. pneumoniae strains using Macrophage RAW 264.7 cells (c) and intestinal epithelial Caco-2 cells (d). Adhesion assay of selected strains using lung epithelial A549 cells (e) and Caco-2 cells (f). Data were analyzed by one-way ANOVA test. Each data point was repeated three times (n = 3). Data are presented as the mean ± s.e.m. * P < 0.05; ** P < 0.01; ***P < 0.001; **** P < 0.0001. Abbreviation: NS, not significant