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Table 1 List of transport systems reported to be involved in tellurite- (abbreviated as Te) and selenite- (abbreviated as Se) uptake by cells of various bacterial species (see text for further details and below for symbols and abbreviations used)

From: Tellurite and Selenite: how can these two oxyanions be chemically different yet so similar in the way they are transformed to their metal forms by bacteria?

Oxyanions Transport systems Bacterial species Method used to define the transport system Results observed Refs.
Tellurite PitA (low-affinity Pi transporter) E.coli pitA gene deletion ΔpitA mutant: increased tolerance to Te [66]
  ActP (acetate permeases ActP1, ActP2) R.capsulatus actP gene deletion ΔactP mutant: increased resistance to Te [64, 65]
  ActP2 R.capsulatus, E.coli Expression of ActP2 from R. capsulatus into E.coli E.coli actP2::lacZ mutant: 4-times higher Te-uptake than w.t [72]
  ActP E.coli actP gene deletion #Active at short-times of exposure to Te [63]
  PitA + PitB (low-affinity + putative Pi transporters) E.coli pitA + pitB gene deletion #Active at long-times of exposure to Te [63]
  PstA, PstD
(high-affinity Pi transporter)
L.lactis §Insertions into pstA + pstD genes Strong increase in resistance to Te [71]
Selenite Pi transporters E.coli Addition of Pi to growth medium Large decrease of Se uptake in Pi amended cultures [92]
  * Undefined sulphate permease E.coli Kinetic analysis of sulphate, selenate and Se uptake Se and selenate compete for a common sulphate carrier [79]
  PitA (low-affinity Pi transporter) E.coli pitA gene deletion ΔpitA mutant: large decrease of Se-reduction rate [92]
  PstA (high-affinity Pi transporter) E.coli pstA gene deletion ΔpstA mutant: decrease of Se-reduction rate [92]
  SmoK protein (ABC transporter like) R.sphaeroides smoK gene deletion ΔsmoK mutant: tenfold increase of MIC for Se [46]
  Pi transporters C.reinhardtii Addition of Pi to growth medium Decrease of Se- uptake in Pi amended cultures [94]
  Mono-carboxylates transporters C.reinhardtii Addition of lactate to growth medium Increase of Se-uptake in lactate amended cultures [94]
  1. *Carrier subsequently identified by others (see [96]) as Sulfate-Thiosulfate SulT permease; #, ‘short- and long-times of exposures’ stand for 5 and 30 min, respectively [63]; §, ‘insertions’ stands for ‘insertional random mutagenesis’ [71]; Se, selenite; Te, tellurite; MIC, Minimum Inhibitory Concentration; Pi, phosphate; PstA, phosphate transport ATP-ase [71]; PastD, phosphate transport permease [71]; ROS, Reactive Oxygen Species; w.t., wild type; Bacterial species: E. coli, Escherichia coli; L. lactis, Lactococcus lactis; R. capsulatus, Rhodobacter capsulatus; R. sphaeroides, Rhodobacter sphaeroides; Rsp. rubrum, Rhodospirillum rubrum; C. reinhardtii, Chlamidomonas reinhardtii