So I was browsing the detoxification metabolistic mechanisms for E. coli, and came across an arsenic detoxification mechanism that converted arsenate to arsenite using a glutaredoxin. So my question is, how does the toxicity of arsenate compare to arsenite? And what is the use of this pathway in E. coli?
I see now.
According to the same website with the reaction mechanism,
Although the arsenite formed is more toxic than arsenate , it can be extruded from some bacteria by EC 188.8.131.52 , arsenite-transporting ATPase; in other organisms, arsenite can be methylated by EC 184.108.40.206 , arsenite methyltransferase, in a pathway that produces non-toxic organoarsenical compounds. cf EC 220.127.116.11, arsenate reductase (thioredoxin) .