2.3.1.189: mycothiol synthase
This is an abbreviated version!
For detailed information about mycothiol synthase, go to the full flat file.
Word Map on EC 2.3.1.189
-
2.3.1.189
-
tuberculosis
-
actinomycetes
-
n-acetyltransferase
-
smegmatis
-
gnat
-
amine
-
gcn5-related
-
thiol-disulfide
-
accys-glcn-ins
-
diagnostics
- 2.3.1.189
- tuberculosis
- actinomycetes
- n-acetyltransferase
- smegmatis
-
gnat
- amine
-
gcn5-related
-
thiol-disulfide
- accys-glcn-ins
- diagnostics
Reaction
Synonyms
MSH acetyltransferase, MSH synthase, MshD, nshD, Rv0819
ECTree
Advanced search results
General Information
General Information on EC 2.3.1.189 - mycothiol synthase
Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
malfunction
production of a Mycobacterium smegmatis transposon mutant blocked in the production of mycothill as the result of lacking the transacetylase activity of mycothiol synthase
malfunction
-
the mycothiol synthase mutant mshD::Tn5, produces high levels of Cys-GlcN-Ins along with two novel thiols, N-formyl-Cys-GlcN-Ins and N-succinyl-Cys-GlcN-Ins, and a small amount of mycothiol. The nonenzymatic reaction of acyl-coenzyme A with Cys-GlcN-Ins to produce acyl-Cys-GlcN-Ins is a facile reaction under physiologic conditions, with succinyl-CoA being an order of magnitude more reactive than acetyl-CoA. The uncatalyzed reaction rates are adequate to account for the observed production of N-succinyl-Cys-GlcN-Ins and mycothiol under physiologic conditions. The N-acyl-Cys-GlcN-Ins compounds are maintained in a substantially reduced state in the mutant but that Cys-GlcN-Ins exists in disulfide forms at 5 to 40% at different stages of growth. Mycothiol is able to facilitate reduction of N-succinyl-Cys-GlcN-Ins disulfide through thiol-disulfide exchange, but N-formyl-Cys-GlcN-Ins is ineffective. The oxidized state of Cys-GlcN-Ins in cells appears to result from a high susceptibility to autoxidation and a low capacity of the cell to reduce its disulfide forms. The mutant exhibits no enhanced sensitivity to hydrogen peroxide, tert-butyl hydroperoxide, or cumene hydroperoxide relative to the parent strain, suggesting that the most abundant thiol, N-formyl-Cys-GlcN-Ins, functions as a substitute for mycothiol
malfunction
-
production of a Mycobacterium smegmatis transposon mutant blocked in the production of mycothill as the result of lacking the transacetylase activity of mycothiol synthase
-