Arsenic - contaminated soil and groundwater pose hazard to zillion of Americans and hundreds of billion of people worldwide . clean up the toxic metal is a laborious and expensive process , with some redress of arsenic reaching into the hundreds of millions of dollars .

A fern –   Pteris vittata ,   also known as the Taiwanese bracken fern – hold promise for reducing both the sentence and monetary value associated with arsenic cleanup . It is unique because it can hyper - accumulate and abide very high grade of atomic number 33 that it take up from the soil , sequestering the toxic constituent in its fronds .

scientist have now determined how this fern does it .   Jody Banks , a Purdue professor of   botany and plant pathology , and her team described the inherited and cellular mechanisms that control the fern ’s arsenic tolerance in a composition write in the daybook   Current Biology . The finding could lead one Clarence Shepard Day Jr. to the modification of other flora that would rectify arsenic from contaminated soils more apace and efficiently .

“ Other research worker have exhibit that this fern , when arise on arsenic - contaminated ground , can murder almost 50 percent of the arsenic in five years , ” Banks say . “ It takes time , but it ’s cheap . ”

Once inside cells - both human and plant – arsenic leads to cell expiry either through oxidative stress or by step in with the cell ’s ability to create ATP , a molecule that allow vigour for electric cell . But the fern has mechanism that guard against these effects .

bank and   Chao Cai , a former graduate student in bank ’ lab , distinguish three gene that are highly fighting when the fern comes into contact with arsenic .   Silencing each of these cistron , they find , guide to last of the plant in the presence of arsenic , exhibit their grandness in arsenic tolerance . By testing the functions of the protein encode by these genes , they showed that these proteins may work together to fundamentally neutralize arsenic once inside the cell .

“ These and other genes work together to mow up arsenic inside a cell until it can be stuff safely away in the cell ’s vacuole where it ca n’t do any trauma , ” Banks said .

The gene program three protein – OCT4 , GST and GAPC1 . Banks and her team showed that OCT4 is a tissue layer protein , check the transfer of compounds through the cell membrane . GST is an arsenate reductase , which serves as a catalyst to turn arsenate from the grease into arsenite , the form of arsenic that can be sequester .

The GAPC1 protein in other plants uses phosphate to help break down glucose for Department of Energy , and arsenate interferes with its normal role . In   Pteris vittata   fern , however , GAPC1 has a higher phylogenetic relation for arsenate than phosphate , earmark the works to tolerate the otherwise toxic inwardness .

Other researchers have discovered a bacterium ,   Pseudomonas aeruginosa , that has a similar ability to tolerate arsenic . The familial mechanisms in the bacteria and the fern are nearly superposable , suggesting that the fern evolved an arsenic tolerance mechanism that is like to that used in bacterium .

“ This fern has co - opted the same mechanism to tolerate arsenic that bacteria use , ” Cai said . “ And it is the only eukaryote that can do this . No plant or animal that we recognize of can do it like this fern . ”

understand the genetic and cellular mechanisms that allow the fern to accumulate and tolerate arsenic is an crucial step in developing other plants that could amend arsenic - foul soils and water supply more quickly .

The National Science Foundation fund this enquiry .

germ : www.purdue.edu