Skip to main content
. Author manuscript; available in PMC: 2009 Aug 19.
Published in final edited form as: Handb Exp Pharmacol. 2009;(190):309–325. doi: 10.1007/978-3-540-79885-9_16

Fig. 1. Metalloid transport in bacteria.

Fig. 1

In both E. coli and S. meliloti arsenate is brought into cells by the phosphate transporters. The first step of detoxification involves reduction of arsenate to arsenite by either E. coli or S. meliloti ArsC (Bhattacharjee and Rosen, 2007). Subsequent detoxification steps in E. coli involves removal of the trivalent form of the metalloid from the cytosol by active extrusion through the As(OH)3/H+ antiporter ArsB (Meng et al., 2004), while in S. meliloti, the AqpS channel facilitates downhill transport of As(III) (Yang et al., 2005). Since arsenite can be taken up directly by cells, using either GlpF in E. coli or AqpS in S. meliloti, the detoxification mechanism functions when S. meliloti cells are exposed to arsenate.