TABLE 3.

Virulence assessment of mutants deficient in genes with enhanced expression during ECC or growth in blood

Challenge type and strainFunctionLog10 median titer 2 days postchallengera in:% Survivalc
Nasal lavage or lungsbBlood
TiterPTiterP
Intranasal challenge
    T4X6.1NA5.6NA10
    T4X SP0090-ABC transporter, permease4.30.003<3.0<0.001100
    T4X SP0092-ABC transporter, substrate binding protein5.70.2784.60.10710
    T4X SP0498-Endo-β-N-acetylglucosaminidase, putative5.50.0265.70.37710
    T4X SP1021-hemK; conserved protein5.70.0884.70.16320
    T4X SP1753-Sodium/dicarboxylate symporter family protein4.50.0114.30.07710
    T4X SP2143-Conserved hypothetical protein5.00.029<3.0<0.001100
    T4X SP2163-PTS system, IIB component5.10.011<3.0<0.00170
    D39X4.9NA7.1NA27
    D39X SP0090-ABC transporter, permease protein4.30.1196.60.52740
    D39X SP2143-Conserved hypothetical protein4.20.1116.90.74827
    D39X SP2163-PTS system, IIB component6.20.2357.00.85213
Intratracheal challenge
    D39X8.4NA9.0NA0
    D39X SP0115-Hypothetical protein8.40.9029.10.5350
    D39X SP0142-Hypothetical protein8.60.8059.10.7100
    D39X SP0641-Serine protease8.31.0009.00.6200
    D39X SP1002-lmb; adhesion lipoprotein7.20.1289.00.6200
    D39X SP1175-Conserved domain protein7.50.2348.60.1810
    D39X SP1434-ABC transporter8.50.3839.20.1650
  • a A total of 12 to 20 mice were used to examine each mutant in both challenge models. Statistical analysis was performed by using a Mann-Whitney rank sum test. Mutant titers were compared to the corresponding wild-type titers. Values in bold face indicate a statistically significant difference. NA, not applicable.

  • b Nasal lavage for intranasal challenge and lungs for intratracheal challenge.

  • c That is, the percent survival 1 week after intranasal challenge or the percent survival 4 days after intratracheal challenge.