Figure 2.

Involvement of HmsB in biofilm formation and c-di-GMP biosynthesis. (A) Crystal violet staining. Y. pestis was grown in 24-well polystyrene dishes, and the bacterial biomass (in vitro biofilms) attached to well walls were stained with crystal violet to determine OD₅₇₀ values. The planktonic cells were subjective to determine OD₆₂₀ values. The relative capacity of biofilm formation of each strain tested was shown with values of 500 × OD₅₇₀/OD₆₂₀. (B) C. elegans biofilms. After incubation of nematode eggs on lawns of indicated Y. pestis strains, the developmental stages of nematodes on each lawn were scored to calculate percentage of L4/adult. (C) Bacterial colony morphology. Aliquots of bacterial glycerol stocks were spotted on LB plate, followed by incubation for one week. (D) Intracellular c-di-GMP concentration. The intracellular c-di-GMP concentrations were determined by a HPLC-MS/MS method, and the determining values were expressed as pmol/mg of bacterial protein.