TABLE 2.
In vivo characterization of replacement mutants
| Mutanta | LD50b | Attenuation levelc
|
|
|---|---|---|---|
| Respiratory tract infection | Otitis media infection | ||
| ΔCO2001 | 3.28 | WT | |
| ΔHOI101 | >5.6 | 1-log unit decrease | WT; 3-log unit decrease in blood |
| ΔIPC009 | 4.08 | WT | |
| ΔIPC012 | >6.26 | 3.5-log unit decrease | 6 log units; undetectable in blood |
| ΔISIP409 | 4.53 | ∼1-log unit decrease | WT |
| ΔISIP454 | 4.65 | ∼WT | |
| ΔISIP456 | 4.84 | WT | |
| ΔISIP485 | ND | ∼WT | |
| ΔISIP497 | 3.69 | ∼WT | |
| ΔISIP069 | ND | ∼WT | |
| ΔISIP741 | ND | ∼WT | |
| ΔISIP870 | ND | ∼WT | |
| ΔOM001 | >5.97 | 4-log unit decrease | 6 log units; undetectable in blood |
| ΔRTI006 | 2.52 | 1-log unit decrease | WT |
| ΔRTI009 | 3.65 | 1-log unit decrease | WT |
| ΔSPIV012 | 2.85 | WT | |
| ΔSPIV013 | ND | WT | |
| ΔSPIV014 | 5.79 | 1-log unit decrease | WT; 1-log unit decrease in blood |
| ΔSPIV015 | 2.9 | WT | |
| ΔSPIV019 | 5.54 | 1-log unit decrease | WT; 4.5-log unit decrease in blood |
| ΔSTS001 | ND | WT | |
| ΔSTS004 | ND | WT | |
| ΔSTS008 | ND | 1.5 log units | |
| ΔSTS012 | 4.40 | 2.5-log unit decrease | WT |
| ΔSTS018 | 3.65 | 2 log units | WT |
| No./totals (%) | 14/25 (56)d | 11/25 (44)e | 2/25 (8)f |
a
Prefix indicates DFI screen in which clone was identified: CO2, carbon dioxide shift; HOI, high osmolarity; IPC, intraperitoneal chamber; ISIP, iron starvation; OM, otitis media infection; RTI and SPIV, respiratory tract infection; STS, static temperature shift.
b
Represents the log value of the LD50. The LD50 of wild-type D39 is approximately 100 organisms. ND, not done.
c
Denotes attenuation level compared to D39 (WT).
d
Number of mutants with LD50 ≥10-fold higher than that of D39.
e
Number of mutants colonizing lungs ≥10-fold less than D39.
f
Number of mutants completely attenuated.