Fig. 6.

Chemotactic ability and receptor clustering in the strong titrator CheW mutant. Strain RP1078 (CheW⁻ Tar⁻ Tap⁻) carrying pVS102 (YFP-CheR) and pPA770 (CheWΔ8) or its strong titrator derivative (CheWΔ8-E154oc) was tested at various IPTG concentrations for chemotactic ability (A) and receptor clustering (B).

(A)Colony size on tryptone soft agar plates incubated for 12 hours at 30°C. The dashed lines show the size of nonchemotactic colonies carrying a CheW⁻ control plasmid (pCJ30).

(B)Fluorescence microscopy cell images as in Fig. 4A and Fig. 5.