FIG. 3.

Whole-cell, solid-phase Tf-binding assay. Whole, iron-stressed gonococci were spotted onto nitrocellulose filters and probed with HRP-Tf (A) or anti-TbpA polyclonal serum (B). Numbering refers to the following gonococcal strains; 1, FA19 (wild type); 2, FA6905 (TbpA⁺ TbpB⁻); 3, FA6747 (TbpA⁻ TbpB⁺); 4, FA6815 (TbpA⁻ TbpB⁻); 5, MCV201 (ΔL5TbpA, TbpB⁺); 6, MCV202 (ΔL5TbpA, TbpB⁻); 7, MCV203 (ΔL4TbpA, TbpB⁺); 8, MCV204 (ΔL4TbpA, TbpB⁻); 9, MCV205 (ΔL8TbpA, TbpB⁺); and 10, MCV 206 (ΔL8TbpA, TbpB⁻). Images were scanned using a Hewlett-Packard ScanJet 6300c. Final images were annotated using Adobe Photoshop 4.0.