This is in contrast to what has been observed for sodB regulation ; overproduction of Fur had little if any effect on sodB expression , presumably because Fur repression of rfrB is essentially complete in these conditions .
This is in contrast to what has been observed for sodB regulation ; overproduction of Fur had little if any effect on sodB expression , presumably because Fur repression of rfrA is essentially complete in these conditions .
In E. coli , expression of sodB is activated by Fur via repression of the small RNA RyhB .