Identification and characterisation of metallothioneins from environmental indicator species as potential biomonitors

Summary

This study has given the first indication that two commonly used environmental indicator species contain members of the metallothionein superfamily. This demonstrates that these species use similar proteins to higher life forms to adapt to heavy metal conditions. Future studies will investigate if the MT proteins are present in the specialised compartments containing high levels of sulphur and copper/cadmium or if other cysteine-rich proteins such as the phytochelatin family are involved. Previously reported functions of the MT proteins in metal homeostasis suggests that MT expression may be up-regulated as a consequence of the high metal concentration of the environment from which these organisms were collected. The use of the MT expression profiles, as sensitive indicators of the metal concentration of the environment, will be investigated.