2011 Fiscal Year Final Research Report
Spx-dependent oxygen sensing mechanism in lactic acid bacteria
| Project/Area Number |
22780074
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Applied microbiology
|
|---|
| Research Institution | Kitasato University |
|---|
Principal Investigator |
|
|---|
| Project Period (FY) |
2010 – 2011
|
| Keywords | 微生物制御 / 発現制御 / 乳酸菌 / 酸素 / 活性酸素 / 連鎖球菌 |
|---|
| Research Abstract |
In thepresent study, we analyzed Spx-dependent oxygensensing mechanism of Streptococcus mutans. Spx is a RNA-binding protein originally identified in Bacillus subtilis. Both SpxA and SpxB of S. mutanswere shown to more strongly bind to alpha-subunit of RNA polymerase when cysteineresidues of these proteins were oxidized. Analysis of cellular Spx degradation pathway demonstrated that SpxB was degraded by ClpXP protease complexwhilecellular SpxA concentrations were constant and not affected by ClpXP protease. Increased concentrationsof SpxB in clpPor clpXmutant didn't affect the expression profileof antioxidative proteins. Theseresultsindicated that the oxidation of cysteineresidues of Spx, rather than cellularSpx concentrations, might play a critical role in oxygen sensing of S. mutans.
|
