FIG. 4.

KT interacts in vitro with TolA, TolB, TolQ, and TolR. Copurification experiments using histidine-tagged purified proteins immobilized on ion metal affinity chromatography columns and periplasmic extracts of tolQRABPal cells carrying the empty vector pIN-III-ompA2 (−) or pKT (+). The immobilized protein is indicated (A3, C-terminal domain of the TolA protein; B, full-length TolB protein; R2-3, periplasmic domain of the TolR protein; Q, full-length TolQ protein; Pal, Pal lipoprotein devoid of its acylated N-terminal cysteine residue; B2-3, periplasmic domain of the TonB protein; none, no protein immobilized). Immunodetected His-tagged proteins are indicated by asterisks. Molecular mass markers (in kDa) are indicated on the left.