. 2024 Jul 9;13(7):825. doi: 10.3390/antiox13070825

Table 1.

Studies on the role of metallothionein in heavy metal detoxification.

Metallothionein Source	Target of Action	Type of Metal Ion	Effect	Reference
Anabaena PCC 7120 NmtA	E. coli cells	Cd²⁺	NmtA-expressing E. coli exhibits better growth at certain cadmium concentrations	[27]
Metallothionein expressed by Alishewanella sp. WH16-1-MT	Rice	Cd²⁺	Increased plant height, spike length, and thousand-grain weight of rice, resulting in a significant reduction in Cd²⁺ content in brown rice, rice husk, roots, and shoots	[28]
S. cerevisiae expresses the PtMT2b gene from Populus trichocarpa	S. cerevisiae	Cd²⁺	Enhanced Cd²⁺ tolerance in S. cerevisiae	[29]
Ipomoea aquatica metallothionein IaMT expressed in E. coli	E. coli	Cd²⁺	Increased tolerance to and accumulation of Cd²⁺ in E. coli	[30]
Rabbit liver MT-2	Grass carp	Cd²⁺	Reduced cadmium levels in kidneys and blood, attenuating organ damage	[31]
Commercial production of metallothionein	PC12 cells	As³⁺	Reduced As³⁺-induced metabolic disturbances and inhibited ROS accumulation	[32]
ShMT expressed in E. coli	Metal ions in solution	Zn²⁺, Cu²⁺ and Cd²⁺	SnMT has a strong ability to bind Zn, Cu, and Cd metals	[33]
Human metallothionein HsMT1L gene expressed in tobacco	tobacco	Zn²⁺ and Cd²⁺	Increased accumulation of Zn²⁺ and Cd²⁺ in tobacco and enhanced tolerance to Zn²⁺ and Cd²⁺	[34]
Metallothionein expressed by the engineered bacterium EcN-MT	Mice	Cd²⁺	Significantly reduced the content of Cd in mouse liver and accelerated the metabolism of Cd	[35]
Metallothionein expressed by Rhizobium leguminosarum strains expressing the pea metallothionein gene	CdCl₂ solution	Cd²⁺	Enhanced Cd tolerance in peas	[36]