Meagher Laboratory Arsenic Phytoremediation Strategies

Arabidopsis plants expressing ECS alone can trap more arsenite and are more resistant to arsenate than wild type.

Plants expressing ArsC alone make even more arsenite than wild type and hence are more sensitive to arsenate.

Plants expressing both ECS and ArsC were the most resistant to arsenate, because they could sequester more arsenic in EC complexes than WT or plants with ECS alone. Two independent trangenic lines expressing both genes lines #1 and #10 are shown in the center of each plate.

The first engineered phytoremediation of arsenic in plants required the enhanced the activity of arsenate redutase (ArsC) in leaves and increased glutamylcysteine synthesis (ECS) throughout the plant.
Arabidopsis plants expressing ECS alone can trap more arsenite and are more resistant to arsenate than wild type. Plants expressing ArsC alone make even more arsenite than wild type and hence are more sensitive to arsenate. Plants expressing both ECS and ArsC were the most resistant to arsenate, because they could sequester more arsenic in EC complexes than WT or plants with ECS alone. Two independent trangenic lines expressing both genes lines #1 and #10 are shown in the center of each plate.
Two genes were required for high level arsenate resistance. The ArsC gene was expressed under control of a light induced ribulose bisphosphate carboxylase small subunit promoter giving activity primarily in leaves. The ECS gene was expressed from a constitutive actin promoter and hence ECS protein was made in all vegetative tissues (leaves, stems, roots).