Table 4.
A brief summary of known/putative functions of the TCSs identified in S. mutans UA159
| TCS Cluster |
TCS protein | GenBank Locus Tag |
Functions | References |
|---|---|---|---|---|
| TCS-1 | HK-VicK RR-VicR |
SMU.1516 SMU.1517 |
Biofilm development, competence development, oxidative stress tolerance, acid tolerance, autolysin production, glucan metabolism, fructan metabolism. | [7,8,10,25,41-44] |
| TCS-2 | HK-CiaH RR-CiaR |
SMU.1128 SMU.1129 |
Sucrose-dependent biofilm formation, competence development, multiple stress response, bacteriocin production | [13,45,46] |
| TCS-3 | HK-CovS RR-CovR |
SMU.1145 SMU.1146 |
Acid tolerance, hydrogen peroxide resistance, murine macrophage killing. | [13,47] |
| TCS-4 | HK-KinF RR-LlrF |
SMU.928 SMU.927 |
Acid tolerance, pp(G)pp metabolism, control of alarmone synthesis. | [48,49] |
| TCS-5 | HK- ScnK RR- ScnR |
SMU.1814 SMU.1815 |
Bacteriocin production*. | [50]* |
| TCS-6 | HK- SpaK RR- SpaR |
SMU.660 SMU.659 |
Bacteriocin production*, self-protection against anti-microbial peptides*. | [51-53]* |
| TCS-7 | HK- PhoR RR-YcbL |
SMU.1037 SMU.1038 |
Unknown. | |
| TCS-8 | HK-KinG RR-LlrG |
SMU.1009 SMU.1008 |
Bacteriocin resistance, substrate transport in cell envelope stress. | [54,55] |
| TCS-9 | HK-LevS RR-LevR |
SMU.1965 SMU.1964 |
Biofilm formation, acid tolerance, fructan metabolism. | [56,57] |
| TCS-10 | HK-LytS RR-LytT |
SMU.577 SMU.576 |
Biofilm formation, oxidative stress tolerance, autolysis, fructan metabolism, cell wall metabolism*. | [58]*, [49,59] |
| TCS-11 | HK-LiaS RR-LiaR |
SMU.486 SMU.487 |
Biofilm formation, acid tolerance, cell envelope stress response, bacteriocin production, bacteriocin resistance, sucrose-dependent adherence. | [38,60-63] |
| TCS-12 | HK-HK11 RR-RR11 |
SMU.1548 SMU.1547 |
Unknown. | |
| TCS-13 | HK-ComD RR-ComE |
SMU.1916 SMU.1917 |
Biofilm formation, quorum sensing, competence development, bacteriocin production. | [9,45,64-66] |
| TCS-14 | HK RR |
SMU.45 SMU.46 |
Unknown. | |
| Orhpan RR1 | RR-GcrR | SMU.1924 | Sucrose-dependent adherence, glucan metabolism, pH homeostasis, competence development. | [67-73] |
In case no knowledge is available on the functions of some TCSs in UA159, reports on homologous TCSs in other microorganisms, preferably Streptococcus species (highlighted by the astral sign*) are provided.