Vitamin C targets (p)ppGpp synthesis leading to stalling of long-term survival and biofilm formation in Mycobacterium smegmatis.
FEMS Microbiol Lett
; 364(1)2017 01.
Article
in En
| MEDLINE
| ID: mdl-27986825
ABSTRACT
Earlier, vitamin C was demonstrated to sterilize Mycobacterium tuberculosis culture via Fenton's reaction at high concentration. It alters the regulatory pathways associated with stress response and dormancy. Since (p)ppGpp is considered to be the master regulator of stress response and is responsible for bacterial survival under stress, we tested the effect of vitamin C on the formation of (p)ppGpp. In vivo estimation of (p)ppGpp showed a decrease in (p)ppGpp levels in vitamin C-treated M. smegmatis cells in comparison to the untreated cells. Furthermore, in vitro (p)ppGpp synthesis using RelMSM enzyme was conducted in order to confirm the specificity of the inhibition in the presence of variable concentrations of vitamin C. We observed that vitamin C at high concentration can inhibit the synthesis of (p)ppGpp. We illustrated binding of vitamin C to RelMSM by isothermal titration calorimetry. Enzyme kinetics was followed where K0.5 was found to be increased with the concomitant reduction of Vmax value suggesting mixed inhibition. Both long-term survival and biofilm formation were inhibited by vitamin C. The experiments suggest that vitamin C has the potential to be developed as the inhibitor of (p)ppGpp synthesis and stress response, at least in the concentration range used here.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Ascorbic Acid
/
Biofilms
/
Mycobacterium smegmatis
/
Guanosine Pentaphosphate
Language:
En
Journal:
FEMS Microbiol Lett
Year:
2017
Document type:
Article
Affiliation country:
India