Table 2. Analysis of selected genes by real-time polymerase chain reaction.
| Gene/locus | Description and putative function1 | UA1592 | TW2962 | Ratio (TW/UA)3 | P value |
|---|---|---|---|---|---|
| SMU860 | Putative ATP-dependent Clp protease, subunit X | 1.17E+06 | 9.88E+05 | 1.18 | >0.05 |
| SMU861 | Putative GTP-binding protein | 8.61E+05 | 9.89E+05 | 1.15 | >0.05 |
| SMU862 | Putative methionine permease | 3.70E+06 | 1.96E+06 | 1.87 | <0.01 |
| SMU863 | Putative homocysteine S-methyltransferase | 7.18E+05 | 2.46E+06 | 3.37 | <0.01 |
| SMU865 | Putative pyridoxal kinase, PdxK | 2.80E+06 | 1.83E+05 | –15.3 | <0.001 |
| SMU.866 | Putative pyridoxal transporter, PdxU | 1.75E+06 | 4.60E+05 | –3.80 | <0.001 |
| SMU867 | ATP-dependent Clp protease, ATP-binding subunit | 2.08E+06 | 2.96E+5 | –7.01 | <0.001 |
| GbpB | Glucan binding protein B | 6.22E+07 | 5.8E+07 | 1.07 | >0.05 |
| SpaP | Multi-function adhesin, also AgI/II and P1 | 4.42E+06 | 1.76E+07 | 4.0 | <0.001 |
| GtfC | Glucosyltransferase C | 3.16E+07 | 3.95E+07 | 1.25 | >0.05 |
| GtfB | Glucosyltransferase B | 1.86E+06 | 7.33E+06 | 3.94 | <0.001 |
1
Description and putative function of the selected genes are based upon the published Streptococcus mutans database.
2
Expressed as copy number of respective transcripts per lg of total RNA. Real-time PCR were repeated at least three times using total RNA from four separate sets of cultures. Data presented here are average of different sets of experiments.
3
Defined as levels of expression in the SMU864-deficient mutant, TW296, relative to those of the wild-type, UA159, with “–” indicating downregulation.