Table 2.
Strain1 | TcpA alteration | Residues in D-region2 | Pilin | Pili | AI3 | AS4 | Pilus:pilus interactions |
---|---|---|---|---|---|---|---|
O395 | Wild type, classical | AAEKDK | + | + | 1.00 | +++ | bundles |
C6706 | Wild type, El Tor | EDAANT | + | + | 0.02 | - | crosshatch/bundles |
RT4340 | O395, tcpAET | EDAANT | + | + | 0.53 | +++ | crosshatch/bundles |
ML7 | RT4524, tcpACl | AAEKDK | + | + | 0.84 | +++ | bundles |
ML10 | C120A | AAEKDK | -/+ | - | 0.05 | - | - |
D-region alterations | |||||||
LC1 | A138E------------------------------------------------- | EAEKDK | + | + | 0.53 | +++ | bundles |
ML15 | ----------A156D--------------------------------------- | ADEKDK | + | + | 1.27 | +++ | bundles/crosshatch |
ML17 | --------------------E158A----------------------------- | AAAKDK | + | + | 2.09 | ++++ | bundles |
ML18 | ------------------------------K172A------------------- | AAEADK | + | + | 2.09 | ++++ | bundles |
ML12 | ----------------------------------------D175N--------- | AAEKNK | + | + | 0.17 | + | bundles |
LC6 | --------------------------------------------------K187T | AAEKDT | + | + | 1.9 | ++++ | bundles |
ML14 | ------------------------------K172A/D175N--------- | AAEANK | + | + | 1.16 | +++ | bundles |
LC7 | ----------A156D/E158A----------------------------- | ADAKDK | + | + | 0.97 | +++ | bundles/crosshatch |
LC9 | A138E/A156D/E158A------------------------------ | EDAKDK | + | + | 0.58 | +++ | bundles/crosshatch |
LC10 | A138E/A156D/E158A/K172A-------------------- | EDAADK | + | + | 0.11 | + | bundles/crosshatch |
LC11 | A138E/A156D/E158A---------------------K187T | EDAKDT | + | + | 0.11 | + | bundles/crosshatch |
LC12 | ----------A156D/E158A/K172A/D175N--------- | ADAANK | + | + | 0.72 | +++ | bundles/crosshatch |
LC13 | A138E/A156D/E158A/K172A/D175N---------- | EDAANK | + | + | 0.04 | - | bundles/crosshatch |
LC15 | ----------A156D/E158A/K172A/D175N/K187T | ADAANT | + | + | 1.52 | ++++ | bundles/crosshatch |
ML16 | A138E/A156D/E158A/K172A-----------K187T | EDAADT | + | + | 0.04 | - | bundles/crosshatch |
LC16 | A138E/A156D/E158A/K172A/D175N/K187T | EDAANT | + | + | 0.04 | - | crosshatch |
ML25 | A138E-----------E158A/K172A/D175N/K187T | EAAANT | + | + | 0.47 | ++ | bundles |
Cavity alterations | |||||||
ML28 | D113G | + | + | 0.04 | - | bundles | |
ML9 | D113A | + | + | 0.07 | - | bundles/crosshatch | |
Combined D-region/cavity mutants | |||||||
DN1 | D113G/A138E/A156D/E158A/K172A/K187T | EDAADT | + | + | 0.08 | - | crosshatch |
DN2 | D113A/A138E/A156D/E158A/K172A/K187T | EDAADT | + | + | 0.08 | - | crosshatch |
All strains contain pMT5.
D-region residues 138, 156, 158, 172, 175 and 187 are listed; underlined residues are the classical-to-El Tor changes; non-underlined residues are the unchanged classical residues; residue 156 is shown in bold type.
AI, autoagglutination index, reported as at fraction of wild type O395 autoagglutination, calculated as the ratio of the inverse of the test supernatant OD600 over the inverse of O395 supernatant OD600 for n=3.
AS, autoagglutination scale: (-), AI of 0-0.10; (+), 0.11-0.20, detectable autoagglutination; (++), 0.21-0.50, moderate autoagglutination; (+++), 0.51-1.50, good or “wild type” (O395) autoagglutination; (++++), ≥1.51, better than wild type autoagglutination (clear supernatant).