FIG 1.

CRISPR3* is a gain-of-function mutation that suppresses ΔpilA, ΔpilB, and ΔsglK in EPS production. Five microliter samples of cell suspensions of various strains at 5 × 10⁹ cells/ml were spotted on CYE-plus-CW plates and incubated for 5 days at 32°C. The photographs were taken under UV illumination. The fluorescence intensity approximates the level of EPS production. (A) CRISPR3* suppresses a pilA deletion. Strains: WT (DK1622), ΔpilA (DK10407), and ΔpilA CRISPR3* (BY802). (B) CRISPR3* suppresses pilB and sglK but not difA or difE mutations. Strains: ΔpilB (DK10416), ΔpilB CRISPR3* (YZ1279), ΔsglK (YZ811), ΔsglK CRISPR3* (YZ1280), ΔdifA (YZ601), ΔdifA CRISPR3* (YZ1281), ΔdifE (YZ603), and ΔdifE CRISPR3* (YZ1282). (C) Expression of CRISPR3 suppresses ΔpilA. Strains: ΔCRISPR3 (YZ1202), ΔpilA ΔCRISPR3 (YZ1200), and ΔpilA ΔCRISPR3 pXY105 (YZ1270). The scale bars in all three panels represent 1 cm.