Phyto-transport and Assimilation of Selenium

TY - CHAP

T1 - Phyto-transport and Assimilation of Selenium

AU - Yu, Xiao-Zhang

AU - Gu, Ji-Dong

PY - 2013/1/1

Y1 - 2013/1/1

N2 - The extensive application and disposal of selenium (Se) have resulted in a significant increase of Se concentrations in the environment, which causes pollution of soil, air, and water as well as the community structure changes of natural ecosystems. Due to the risks to the health of humans and the environment chiefly associated with industrial discharges, Se remediation of contaminated sites is of crucial importance in environmental cleaning up. Se removal using physical, chemical, and engineering techniques is complicated and expensive, but phytoremediation is energy efficient, aesthetically pleasing method, in which plants scavenge Se from the contaminated sites, accumulate it in the biomass, or volatilize gaseous forms of Se into the atmosphere. Different plants vary considerably in their physiological and biochemical responses to Se considering tolerance, uptake, accumulation, and volatilization of Se. Due to the similar chemical properties between selenate and sulfate, selenate is chiefly absorbed by roots through the sulfate transporter. Selenite uptake seems to be driven by passive diffusion. Selenate is accumulated in selenate-supplemented plants, whereas selenite can be readily metabolized to organic Se. The enzymatic reduction of selenate in the presence of ATP sulfurylase appears to be a major rate-limiting step for the selenate-volatilization processes. Therefore, overexpression of ATP sulfurylase in transgenic plants is expected to increase the assimilation of selenate into selenomethionine (SeMet) before the volatilization of the generated gaseous Se of dimethylselenide (DMSe) into the atmosphere. Because the volatile DMSe is much less toxic than other species of Se, phyto-volatilization is a suggestive remediation strategy for phytoremoval of Se from the contaminated soils.

AB - The extensive application and disposal of selenium (Se) have resulted in a significant increase of Se concentrations in the environment, which causes pollution of soil, air, and water as well as the community structure changes of natural ecosystems. Due to the risks to the health of humans and the environment chiefly associated with industrial discharges, Se remediation of contaminated sites is of crucial importance in environmental cleaning up. Se removal using physical, chemical, and engineering techniques is complicated and expensive, but phytoremediation is energy efficient, aesthetically pleasing method, in which plants scavenge Se from the contaminated sites, accumulate it in the biomass, or volatilize gaseous forms of Se into the atmosphere. Different plants vary considerably in their physiological and biochemical responses to Se considering tolerance, uptake, accumulation, and volatilization of Se. Due to the similar chemical properties between selenate and sulfate, selenate is chiefly absorbed by roots through the sulfate transporter. Selenite uptake seems to be driven by passive diffusion. Selenate is accumulated in selenate-supplemented plants, whereas selenite can be readily metabolized to organic Se. The enzymatic reduction of selenate in the presence of ATP sulfurylase appears to be a major rate-limiting step for the selenate-volatilization processes. Therefore, overexpression of ATP sulfurylase in transgenic plants is expected to increase the assimilation of selenate into selenomethionine (SeMet) before the volatilization of the generated gaseous Se of dimethylselenide (DMSe) into the atmosphere. Because the volatile DMSe is much less toxic than other species of Se, phyto-volatilization is a suggestive remediation strategy for phytoremoval of Se from the contaminated soils.

KW - Indian Mustard

KW - Keshan Disease

KW - Hydrogen Selenide

KW - Dimethyl Diselenide

KW - Seleniferous Soil

U2 - 10.1007/978-3-642-35564-6_9

DO - 10.1007/978-3-642-35564-6_9

M3 - 章节

BT - Plant-Based Remediation Processes

PB - Springer Berlin Heidelberg

ER -