S-bacillithiolation protects conserved and essential proteins against hypochlorite stress in firmicutes bacteria.
Antioxid Redox Signal
; 18(11): 1273-95, 2013 Apr 10.
Article
in En
| MEDLINE
| ID: mdl-22938038
ABSTRACT
AIMS:
Protein S-bacillithiolations are mixed disulfides between protein thiols and the bacillithiol (BSH) redox buffer that occur in response to NaOCl in Bacillus subtilis. We used BSH-specific immunoblots, shotgun liquid chromatography (LC)-tandem mass spectrometry (MS/MS) analysis and redox proteomics to characterize the S-bacillithiolomes of B. subtilis, B. megaterium, B. pumilus, B. amyloliquefaciens, and Staphylococcus carnosus and also measured the BSH/oxidized bacillithiol disulfide (BSSB) redox ratio after NaOCl stress.RESULTS:
In total, 54 proteins with characteristic S-bacillithiolation (SSB) sites were identified, including 29 unique proteins and eight proteins conserved in two or more of these bacteria. The methionine synthase MetE is the most abundant S-bacillithiolated protein in Bacillus species after NaOCl exposure. Further, S-bacillithiolated proteins include the translation elongation factor EF-Tu and aminoacyl-tRNA synthetases (ThrS), the DnaK and GrpE chaperones, the two-Cys peroxiredoxin YkuU, the ferredoxin-NADP(+) oxidoreductase YumC, the inorganic pyrophosphatase PpaC, the inosine-5'-monophosphate dehydrogenase GuaB, proteins involved in thiamine biosynthesis (ThiG and ThiM), queuosine biosynthesis (QueF), biosynthesis of aromatic amino acids (AroA and AroE), serine (SerA), branched-chain amino acids (YwaA), and homocysteine (LuxS and MetI). The thioredoxin-like proteins, YphP and YtxJ, are S-bacillithiolated at their active sites, suggesting a function in the de-bacillithiolation process. S-bacillithiolation is accompanied by a two-fold increase in the BSSB level and a decrease in the BSH/BSSB redox ratio in B. subtilis. INNOVATION Many essential and conserved proteins, including the dominant MetE, were identified in the S-bacillithiolome of different Bacillus species and S. carnosus using shotgun-LC-MS/MS analyses.CONCLUSION:
S-bacillithiolation is a widespread redox control mechanism among Firmicutes bacteria that protects conserved metabolic enzymes and essential proteins against overoxidation.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Stress, Physiological
/
Bacillus
/
Bacterial Proteins
/
Hypochlorous Acid
/
Cysteine
/
Glucosamine
Type of study:
Prognostic_studies
Language:
En
Journal:
Antioxid Redox Signal
Journal subject:
METABOLISMO
Year:
2013
Document type:
Article
Affiliation country:
Germany