9.B.105.1.1
PbrB/C fusion protein of 358 aas and 10 - 12 TMSs. Confers resistance to Pb²⁺ (Taghavi et al., 2009).  May be a phosphatase. While PbrA non-specifically exported Pb²⁺, Zn²⁺ and Cd²⁺, a specific increase in lead resistance is observed when PbrA and PbrB are coexpressed. Possibly Pb²⁺ is exported from the cytoplasm by PbrA and then sequestered as a phosphate salt with the inorganic phosphate produced by PbrB. Similar operons containing genes for heavy metal translocating ATPases and phosphatases can be found in many different bacterial species, suggesting that lead detoxification through active efflux and sequestration is a common lead-resistance mechanism (Hynninen et al. 2009).